Hmm, I keep my CA cichlids at around 80* in the summer (it gets hot on 3rd floor where tanks are) with seemingly no ill effects. I have had them at 86* for a week or two as well to treat ich. I would be a little surprised if that is what killed him, though anything is possible I suppose.
It won't kill them immediately, but exposed to these temps over time it might. Luckily this summer has been pretty cool and my temps are staying around 75f.
I would love to move the tank in my basement, because it would be so much cooler. Winters it gets cold though. I would have to start running heaters again.
