I recently had a fermented in the fridge, and I didnt realise how cold it was in there............I FROZE MY BEER!
It wasnt solid, more like a slushy.
So I bottled one, then turned the fridge dial up and continued to lager.
The bottled one carbonated in around 2 weeks, so I bottled the rest and they are fine.
Also, I have pitched at 36*C before, and that didnt kill the yeast either.
It seems like whatever I do, I just cant kill the yeast........so Heals, I wouldnt worry. But If you asked me, I'd have it fermenting at 18-20*C.