Here are the ones I have, both before and after the date on the $100. I guess the answer is although the owner's name changed on the records, the casino name didn't.

No explanation of why the 100 was dead and buried in plastic. Not because of how it was marked. Not because of a casino name change. Not because the casino closed (it was still there in 1993 anyway).

So I just don't know. Nice to know it was approved, though.