Not even close. Not even 800. If I were to guess maybe a little over 700. Never saw any singles from him in pics or video though.
Did he do a single at the WBF event?
Biggest squat I heard for Platz was #765, during the time he was going back and forth with Hatfield. It was at the 1993 FIBO, Platz got #765, Fred got #855. Fred mentioned that Kaz was helping him, by bracing him at the bottom during the max squat. During the same event, Platz did the #23 rep with #500ish. Fred got 12 or so with that weight.
Also, they were using suits, so #700 max would be close.