The Bible speaks of dogs who don't bark---rather scathingly, at that. Those priests and bishops who were ordained or consecrated using the false/invalid prescription are not priests or bishops. Some (only God knows how many) among the NO are valid priests and bishops. Gives one a headache doing the math and guessing if their entrance to the office pre or post dated the change.
But even still, those in the NO are part and parcel of a heresy, so there is still great danger in listening to them, although the command to obedience is still in effect with the valid clergy. It's a nightmare, hazardous to your mental and spiritual health. I avoid it if at all possible and cling to my good CMRI bishop, seeking his counsel as much as I can.
Bottom line for me regarding the talk, talk: pray and do penance or at least offer up whatever little sufferings I have and pass on whatever info may help others. Another point comes to mind about all this and the other threads on today's stinkin' thinkin'. We may not achieve decontamination in this life, and if we do I am inclined to consider it a miracle. We are simply too steeped in weird attitudes and error.