Miltonia care question

[Yourneedfulthings]

I was passed a mitonia that has been neglected.
I re potted it in medium/ small orchiata and sponge rock mix in a plastic pot. Growing new shoots and roots. Now that it is blooming and my greenhouse has become hotter up 90's, 60% humidity, the blooms do not open completey and some of the new growing shoots leaves turn yellow/ brown/ soggy. I can not figure out when it need water.
I took it into my home to try cooler temperature and the blooms completely dry out.

Can some one tell me what this plant wants.? I have two other small miltonias that are doing ok.