Just out of curiosity, why would anyone desire to know this information? Surely, you can trust your priests and bishops, can't you?
Even when they pray to John XXIII or John Paul II?
If your priest is an Ecclesia Dei (FSSP, ICRSS, etc.) priest, just what do you expect him to do? Reject the Conciliar church? If he did that he'd be...well, he wouldn't be FSSP, ICRSS, or any other Indult priest.
So I repeat my question, what possible reason might you have for not trusting your priests or bishops?
P.S. Praying to these men would not invalidate their orders. (Not having valid orders in the first place is a whole different issue--but, if you worship with the Conciliar church, does it really matter?) Besides, if you doubt the validity of their orders, doesn't that make you a...a...oh! I just can't say it! It's just too terrible to contemplate!!! :scared2: