Growing Egret Orchids from Bulbs - Habenarea

[HiOrcDen]

So a while ago I received a few Egret Orchid bulbs. One variety the standard, and one a variation called Hisyo.

I kept the bulbs (sorry if bulb is not the correct term) in the refrigerator in a humid container for a few days. Three bulbs of one variety started putting up a sprout, maybe a few millimeters.

I planted them a few days ago, but I think I may have used too much pumice, because it dried quickly. One of the buds may have died, brown at the tip. One sprout is turning green, but not growing.

I also planted the bulbs only deep enough to allow the sprout to stick out above the surface. I keep them outside in a water dish to keep the mix damp.

In order to get them growing, should I bury the buds deeper? Should I repot without little or no pumice, maybe vermiculite and perlite instead? (or another mix?) Should I pop them back into the fridge till they grow a bit more?