I have seen this sort of thing before also,
and concur with others. The media seems to have been kept so moist that it is growing fungus on it. Whether it is the Trichoderma is another question however. I have some pots where the tricho is growing on the surface, which looks gross & repels water a bit from the webbing", but does no other harm (yet).
When using tricho, perhaps make a small depression & pour into that, to prevent spreading "spores/growth" on the surface.
At first thought I would say that from the look of what you have, it appears that the media is kept too moist & hence growing "bad fungus", HOWEVER, after looking closer, I would have to admit that I can't make that assumption! It does also look a bit like what I have seen when the Tricho starts growing on the surface, but only when I have drenched the entire surface or poured granular type on the top of a pot instead of mixing it in toward the bottom/middle of the media.
I am curious to know what your set-up looks like. These are not "swamp plants" & don't need to get soaking wet. If through watering or humidity they stay too wet, fungus like this will also take hold on the media. And a LOT depends on your media... what kind of wood chips did you use? Are you sure they are what you think they are? (Sometimes for "mulch" they will sell combination's or you can get other woods mixed in, which can "rot" very quickly.)
And in years past, I have even had dead LFS get like that when conditions were poor or when part of the mixture caused fungus that took hold on other things like the LFS.
As you are the grower, only you can figure out what the situation is & what conditions may be causing this. Above all, since you may have a replacement coming, you should figure out what to do before you have a similar situation with your new plant.
While it may be healthy coming in this next time, the conditions you grow it in will be what determines its ultimate success.
As you know these are not beginner plants, and so the necessary "tweaks" in environment may be very small or very hard to create for them. Sometimes a little bit off can be enough to spell disaster...
Good Luck! Many of us have been where you are with this, and it is all a part of learning what to do & how to do it.