There is a pretty interesting thread on reddit about Disney tunnels. I read the whole thing quite a while ago, but don't remember how I found it
Kek!
Found it pretty quick. Hadn't thought to use search engine when I was looking for it a while back
https://www.reddit.com/r/nosleep/comments/30alk5/i_was_an_undercover_security_officer_at_walt/
Here are a few more. I don't remember the details , but I went down this rabbit hole a while back when I couldn't sleep. Entertaining if nothing else. I remember hoping for an update.
https://www.reddit.com/r/AskReddit/comments/7oklbk/what_is_a_disney_world_secret_that_you_know/
https://www.reddit.com/r/AskReddit/comments/3h9oi2/workers_of_disneylandworld_what_is_the_coolest/