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I haven’t studied sacramental theology much so I don’t know about what constitutes moral certainty about the intention of the minister but it seems to me that it should be theoretically impossible for a minister to deceive the public about his intention.  How can you have an intention to not do what the Church does when you have an intention to appear to be doing what the Church does?  The only way I can think of to do that is to not be a valid minister but only to appear to be a valid minister.  Otherwise, I don’t see how a valid minister could form the intention to deceive without actually having the intention to do what the Church does. It is possible to perform the ceremony without intending to do what the Church does but only if you publicly state your intention so that you aren’t actually doing what the Church does.  If you don’t state it publicly then you actually did do what the Church does and even if you didn’t initially intend to do what the Church does, you ended up doing what the Church does intentionally.

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That's an interesting way of looking at it, although I don't think sacramentalists look at it that way.  They always admit the possibility of sacrament simulation (something most moralists at least touch on).  Theoretically it is certainly possible, and grievously sinful, of course.  Maybe a decent way to think about how it can be possible is to think about the Church's marriage laws.  One cause for nullity of marriage is when consent is lacking-- not the Novus Ordo "they didn't know what they were getting into" type way, but in the real and substantial way: someone who says "I do" while very explicitly, at the same time, saying "I don't" internally. 
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Now, marriage is a sacrament, the validity of which is the responsibility of the marrying couple.  Withholding intent to marry is synonymous with withholding intent to baptize or any other sacrament.  And the Church recognizes, indeed even builds into her law, the possibility for intent to be explicitly withheld despite the outward appearance.  So I think we can't get very far contending that it is theoretically impossible to withhold intent.
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Of course, in the moral order of things, one shouldn't be scrupulous about such "possibilities."  The reason these "possibilities" even cause problems to begin with is that modern man, including modern Catholic man, is accustomed to thinking materialistically-- he thinks that there are things which are 100% certain (like the laws of nature or the laws of God) and then there are varying degrees of "not 100% certain."  But that's not how Catholic theologians have ever viewed certainty, as though it were a composite on a quantitative scale.  That's a modern corruption, and it might be suitable for empirical sciences, but it is not suitable for anything else, including daily-decisions of even the mundane variety.  Moral certainty is true certainty.  It's not 99%, 100%, 45%, etc. "type" certainty.   We should try our best to disavow ourselves of thinking of certainties in this way.

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That's an interesting way of looking at it, although I don't think sacramentalists look at it that way.  They always admit the possibility of sacrament simulation (something most moralists at least touch on).  Theoretically it is certainly possible, and grievously sinful, of course.  Maybe a decent way to think about how it can be possible is to think about the Church's marriage laws.  One cause for nullity of marriage is when consent is lacking-- not the Novus Ordo "they didn't know what they were getting into" type way, but in the real and substantial way: someone who says "I do" while very explicitly, at the same time, saying "I don't" internally.  
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Now, marriage is a sacrament, the validity of which is the responsibility of the marrying couple.  Withholding intent to marry is synonymous with withholding intent to baptize or any other sacrament.  And the Church recognizes, indeed even builds into her law, the possibility for intent to be explicitly withheld despite the outward appearance.  So I think we can't get very far contending that it is theoretically impossible to withhold intent.
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Of course, in the moral order of things, one shouldn't be scrupulous about such "possibilities."  The reason these "possibilities" even cause problems to begin with is that modern man, including modern Catholic man, is accustomed to thinking materialistically-- he thinks that there are things which are 100% certain (like the laws of nature or the laws of God) and then there are varying degrees of "not 100% certain."  But that's not how Catholic theologians have ever viewed certainty, as though it were a composite on a quantitative scale.  That's a modern corruption, and it might be suitable for empirical sciences, but it is not suitable for anything else, including daily-decisions of even the mundane variety.  Moral certainty is true certainty.  It's not 99%, 100%, 45%, etc. "type" certainty.   We should try our best to disavow ourselves of thinking of certainties in this way.

#38 and #39 was me.  I intended to check the box but I didn't.  Get it?  Actually, if truth be told, I never did intend to check the box.  I may have desired to check the box but I didn't intend to.  If I had intended to check the box, I would have at least made an attempt to click the box.  But I didn't even make an attempt.  My bad.  Could a murder suspect claim that he never intended to murder the guy?  Yes, he could but if the murder was accomplished by some elaborate scheme then the judge/jury will come to the conclusion that he actually did intend to murder the guy.  So while I agree that a sacrament can be simulated, I disagree that it could be simulated merely by having/entertaining a thought about simulating it.  In order to actually simulate a sacrament, you have to take some steps to achieve a simulation.  If you don't take any steps to achieve a simulation then you never actually intended to simulate it (even if at some point you desired to simulate it).  Performing a sacramental ceremony cannot be a simulation by default.  Rather, if all the external requirements for validity are met then it is valid by default.  The intention must have been there or it would not have happened as it did.  I think intention is a pretty low bar to meet.  On the other hand the form and matter have to be correct.  Have you ever heard a priest repeat the words of consecration?  I have.  It is disconcerting to think that a mispronunciation of Latin could invalidate the sacrament but it could happen if the mispronunciation is bad enough to change the meaning.  When I am serving I listen to the words but I don't worry about it because I also would not go to a Mass by a priest who was obviously incompetent or untrustworthy.  I think I would be very scrupulous about a baptism performed by a non-Catholic.  I would want to be absolutely certain that they used the correct form and matter.  But I would trust a good priest even if I was not a witness of the form and matter.