That’s probably it, morels have a rather short shelf life because they autolyze (or whatever the fancy term is for “start digesting itself”)
That process needs to be halted if you want them to last more than a day
Edit: found that out when the GF realized that I have a green house and grow (most) my own veggies- and compost the waste back into grow-juice. (Fortified with certain other things.)
She was going to beg, but I apparently rolled over too quickly. (She now has three racks that hold compost at various stages specifically to grow mushrooms.)