Thank you very much! Yes, we will try at 88F next time. My boyfriend's mentor advised him to incubate at 90F when he was starting out (and he himself did 90F), and he's never had issues until now. But we were using homemade mini fridge incubators, which I imagine are much better insulated against fluctuations. (And in all honesty, over the years of our own learning and experience, we started to question some of the practices of his mentor and advice he gave... He seemed to care a lot less about his animals than he said he did... It doesn't surprise me at all to hear that 90F is riskier)
Thank you again!!