Just ask yourself if major airlines consider your experience in Pinnacle or MESA as valid experience to hire you, I think that they do since PCL pilots have moved on to greener pastures without a problem, so if the answer evidently is yes, then so their training records are consider valid. You also said that failures are rare at majors, how do you know that? training records are not available to anyone outside of the training departments and just because pilots don't come here and cry the blues about how the checker was unethical and busted me, how dared he? that doesn't mean they do not happen.
Other pilots that have busted a ride before have gone on to major airline jobs, but I can guarantee you that none that have your attitude has.
Its been a while...but I didn't think they could give you compound failures on a "jeopardy" checking event?
If that is even what happened, In my experience as a check airman I have learned that individuals explaining their bust are always presenting an "Iceberg" they only show a small portion of the event usually reconstructed to make everything else but them to be at fault but you don't see what is under the water line, usually twice as large as what they show