Employer appealed unemployment-changed story during hearing?

I was terminated back in October, alledgedly for misconduct; they claimed I tried to falsify the drawer report to cover a short, which wasn't true...I had noticied the short and called the GM, who TOLD me to void the order that caused the short. I was approved for unemployment, as the state said they failed to prove misconduct. My ex-employer appealed this (of course), and when I received the paperwork from my UI file, it pretty much backed up what I had told them during my initial review...that I was let go because of that incident. They didn't present any new evidence, and I never received anything before my hearing, so I prepared based on that. I had only had one performance review, where nothing bad was said, and I even got a raise.

So, this past Tuesday, I had the appeal hearing. The GM who let me go showed up (wasn't notified he'd be on the call), and he proceeded to tell an ENTIRELY different story than what was in the paperwork; primarily that they had "noticied" questionable voids in the past (I'd only worked there 5 months), that I had been coached on these (even though that wasn't their policy...their policy said unverifiable voids are an automatic termination), and that they had continued. He presented NO documentation of ANY of this, probably because it didn't exist. I objected to the testimony, mainly because nowhere in any of the statements or paperwork they submitted had they laid this out, and had I known they were going to go this route, I could've provided documentation refuting this. I DID ask that the separation statement (which i didn't sign), be admitted into evidence, as it stated that there was only one incident that caused my termination.

My question is this: Did my ex-employer basically sabotage himself, by turning it into a matter of performance rather than misconduct, and by not submitting ANY supporting documentation of his claims?