Firstly, welcome to the board.
Next to the problem. There could be a couple issues. I really don't understand the potting setup from what you said. Miltonias seem to want a steady supply of water while in growth and while blooming. (Darned if I can figure out how to do that
) So it's possible that daily watering is more suited to your plant.
Another issue is that some others have indicated problems with Miltonias this particular season while others are displaying gorgeous photos of blossoms. My personal plant has always done fine, but this year did as you say - spikes blasted, blossoms didn't open fully, etc. Wish I could say: fix this and you'll be good to go, but I think there are two many possibilities.