Cool dessicant drying is not the best way to dry mushrooms. It?s much better to first dry them in front of an computer fan for 1 day, then they are already preaty dry, then end dry them on dessicant.

Is your dessicant fresh(not waterlogged already)?
If they smell, they are probbably rotten. Would?t eat them then.

and they have a kind of sponge like consistency inside

they dont smell rotten, they smell mushroomy, with a faint sugary smell

From your description they sound fine.

by the way, if anyones interested, i rang a couple of professional mushroom growers, and they said that getting mold on your substrate is likely and if it bothers you you can cut it off but it cant make any difference to the mushrooms.