We need to really think deeply about this, and it will all become clear.
Would Fr. Zendejas (for example -- feel free to replace his name with any other valid Trad priest) EVER be in this position, even if the bishop who ordained him (Bp. De Galarreta) passed away tomorrow and then 20 years passed?
No, there would still be tons of places he worked for years, plenty of witnesses to his ordination, plenty more who saw it in the Verbum that year (1989), etc.
So even being old is no excuse for "all my witnesses are dead, and hello, of course the bishop who consecrated/ordained me is dead."
Well there should be priests/bishops who can vouch for your ordination/consecration.
And let's not forget the most basic thing: All we need is ONE docuмent to prove ordination and ONE docuмent to prove consecration. Everything else is fluff, or actually CHAFF (material ejected from fighter jets to confuse heat-seeking missiles, so they chase after and destroy a piece of the chaff instead of the plane itself) Most grains of chaff are wasted. But that one blessed, blessed piece does the job and diverts the missile, and all the expense of the whole "load" of chaff is more than covered, since the jet was saved from destruction.
Note that ALL liars, deceivers, and even those who just have something to hide, engage in this. If you don't throw around a bunch of talk, people will focus on the lie, which is A) uncomfortable and B) dangerous. That's why liars are very talkative.
Please correct me if I'm wrong, but haven't ALL voices from the past been emphatically negative about Ambrose Moran and his "story"? Yes, a single layman (who never saw his ordination or an ordination certificate) vouching for him as a priest wouldn't be much proof -- but do we even have that?
The only people we've been able to contact have been firmly in the negative about Ambrose.