This thing looks far too much like a digestive tract for me to ever consider going inside it willingly. I suppose after direct observation for a while I might be more comfortable with the creature but I feel like I'd never get past that initial feeling...

It reminds me of a particularly fantastic piece of lore from Skyrim. It's remarkable to come across in real life something similar to what stretched my suspension of disbelief in a fictional setting.

"The Underground Express was a method of transportation employed by the native Argonians in Black Marsh. It involved travelers submerging themselves into a Rootworm's stomach through their breathing holes. The travelers could then leave the Underground Express via the breathing holes as well. The travelers would then travel inside a Rootworm's stomach during their migrations. Notable exits and entrances to the Underground Express during the winter could be found at Gideon and Hixinoag."

- The Argonian Account, Book III

https://elderscrolls.fandom.com/wiki/Underground_Express

We could send a small remote controlled submersible vessel through it. Get some lights in there and see it from the inside out.

Just looking at the picture that had that caption: NOPE