I’ve grown oyster mushrooms from the grocery store on used coffee grounds and I mixed things with my hands in open air. Take the cakes out of the jar. Put them in your fruiting chamber (or plastic bag draped over it). The mycelium is a little plant animal and it breathes oxygen. You’ve stuffed it in an airless room with a tiny little hole. The whole body needs to be able to breathe. Not just the elbow.