Good to know, but this is not a refutation of what is actually held by BOD/BOB proponents.
This tells a Minister what HE must do before giving Water Baptism. He cannot stop short with the basic idea of God and His goodness and pour.
This does not say what God must do, or not do, in enlightening a soul with His grace or granting the grace of Justification, or Salvation in either Testament.
Of course a minister must teach, govern and sanctify properly in all circuмstances. Such a basic concept of God and His Goodness is the least that an uninstructed pagan must arrive at to qualify for BOD. He must have at least that much of a concept, and the Grace to believe it, and intent to live accordingly.
You're (deliberately?) ignoring the part in there where the Holy Office declares belief in the Holy Trinity and Incarnation to be necessary by necessity of means (for supernatural faith). That's the exact language being used in this debate among theologians.
Yes, this is a practical directive ... but it gives an explanation for the theological reason behind it. Basically, it's saying that Rewarder God theory cannot even be entertained as a POSSIBILITY in the practical order.
So this is even a stronger statement that one might imagine. Normally one may confer Baptism on a dying person in a doubtful scenario, if you think there's SOME chance that the person has the right dispositions. So, for, instance, if there's a dying unconscious person, the priest typically asks, did the person give ANY sign before going unconscious of possibly wanting to be baptized? There needn't be absolutely certainty of the right disposition, but there needs to be some indicator. In other words, even in a doubtful scenario, so long as there's some possibility, the person may be baptized. Here, this directive is tantamount to saying, "there's no chance that this suffices for supernatural faith" so you can't even baptize such a person in danger of death.