So I have 3 hermit crabs, at the end of 2023/beginning of 2024, two of them went underground to molt. It's now November 2024 and the 2 are still underground and I've read that they probably died

I could've sworn I saw one of the two the other week but when I looked again it was the same one that's always above ground so I'm not too sure but at the very least one has been underground for almost a year

so today I went to clean some surface sand and there were these long clumps and I found through washing out the sand I pulled out, and also pulling off the COCOON ITSELF with the maggot inside from a piece of wood, that yeah I have these maggots in the sand, different sizes some pretty large. I took pictures of the one I pulled off the wood and it's large and has a brown head. I wasn't able to find anything about this besides like fly larvae and these don't seem like it. please help

I have my surface crab separated for now for safety.