He has been consistent through the years with the 500 bench claim. I don’t remember hearing the squat number though.
It’s amazing that at 19 he decided it wasn’t in his best interest to push his strength to the limit and to only focus on reps/despite using large amounts of anabolic compounds.
I've also don't recall that squat claim. And I've been following Jay long enough that I would think I would have heard it by now...
His bench press has been verified, as you said.
I think if we're talking about a squat to above parallel, that maybe it could be possible. Maxime Boudreault is the strongest man in my city and placed 3rd at world's last year, and even he "only" squats 845-lb to proper depth. And strength is what Max does as a career. I can't imagine Jay getting 700 below parallel at 19, when he only started training at 18.
But he was very strong, very young. Clearly a genetic freak. Just that 700 seems a bit much. That's an elite lift at 19.
To your last paragraph - are you suggesting Jay should have pursued powerlifting instead?