Even less helpful, the loan providers aren't satisfied with getting ratings from one or two agencies, but they must have all three (and they have no idea how to solve the PIN problem either, don't ask for help from the experts).
TransUnion was by far the best of the rating agencies - after just 20 minutes of dialing menus, I got a human who asked a few questions to establish my identity and then lifted the freeze (for a fee). Never found a human at Experian, but an exhaustive search of my papers turned up the PIN. Even then, dial-a-menu didn't work until I realized they were verifying my PIN with street numbers from my old address of over three years ago instead my current address - so much with their providing accurate info.
Equifax was the biggest problem because I never found their PIN or reached a human there. Fortunately my wife had purchased some credit product from them and was able to reach a human, who in turn gave us THE SECRET PHONE NUMBER TO CALL A HUMAN AT EQUIFAX FOR SECURITY FREEZES:
Who knows how long that number will be good. Maybe they've already changed it, like Al-Qaeda does.
Even the SECRET PHONE NUMBER wasn't perfect though - they still wouldn't permanently lift the security freeze without a PIN, but it occurred to me to ask for a temporary lift, and after answering a million questions semi-accurately about my identity, they granted me this boon.
So, lessons for others from my failings - if you place security freezes, don't lose your PINs!! If you have lost them, start the snail mail process for requesting new ones, regardless of whether you need a loan in the near future. And if you've lost your PINs and are planning on getting a loan in the near future, start dealing with this immediately, and don't expect any help from the experts.
And don't forget to have fun!