This needs to be told a lot more. You do not and should not need to keep substrate damp. It promotes bad bacteria, mold, yeast, etc and is not good for a snake to live on. Sphagnum moss in clumps in the corners does an amazing job to get humidity where it needs to be and keeps your cage from being a swamp
Thanks! I should also mention that I change the moss regularly and soak the dishes in mild bleach before running them through the dishwasher once a week on the hot cycle (no soap) to rinse.
No cage is too large - nature is the best template - a snoot can't be booped too much