I know that having mushrooms growing in my pile is fine, but does having them there say anything about it's correctness regarding C:N and moisture?
I think your compost is a bit too wet. Whenever I find mushrooms growing on my property, I figure I've been watering that area too much. I step the mushrooms into the ground, cut back on water, and the mushrooms don't come back.
My mushrooms don't talk. They just sit there silently, looking cute.
Sounds like you may have refractory materials like wood or other high lignin content material. As the link points out, not all carbon is created equal.
Here is a link that might be useful: The Effect of Lignin on Biodegradability
When I was in college, somebody once told me that if you ever wake up with bullfrogs on your mind, it's a sure sign that you have bullfrogs on your mind (I think alcohol may have been involved).
For some reason, though, his statement has stuck with me and I've been able to apply it to other situations.
Maybe the mushrooms in your compost are a sign of mushrooms in your compost. In other words, it may be that sometimes a cigar is just a cigar.
Mushrooms growing in a compost pile indicate the the fungi are busy working and the environment of that growing medium is good for them. Since mushrooms only grow in moist soils that may indicate that you compost is too wet for the bacteria to be working.