Yep, that's why I already did a big purge of moss that didn't have mushrooms in it but I could see the mycellium spreading in it.It's important to remember that mushrooms are the fruiting bodies of undersubstrate fungus. The fungus must have spread from your U. humboltii into the substrate that you have under the plants and then up into your pots.. This would explain why it's popping up everywhere
I don't use any fungicides / pesticides at my place cos of my terrarium critters (tarantulas, crabs, mantids, etc), have heard rumors that even using the stuff in the same room is bad because of air circulation carrying it from one area to another and my room like like a wind tunnel, two room fans and an AC. I prefer not to risk it. If I need to kill bugs on a certain plant I use isopropyl alcohol.
Seems like the idea behind Trichoderma is to stop one fungus with another. I got a few plants from a TF member who was really into the Trich and her pots turned green and gross long before any other I've ever had. I dunno if it's cos I didn't continue dosing the plants or what but that was na-stay!might be good application for trichoderma
I'll just repot on Tuesday with some fresh moss and cross my digits I'm able to get rid of the sneaky mycellium.