Edgar glitches in Kefka's end speech

Hmm, I have used Zone Doctor to move the Sprint Shoes in Narshe... But this particular bug crops up in the vanilla ROM I don't believe I ever opened with Zone Doctor, though I might be mistaken about that, and I also didn't test the vanilla ROM with Zsnes or anything other than Snes9x.

What other corruptions occur from using Zone Doctor? I thought the corruptions people warned about were the possibility of making the whole ROM buggy/crash.