And just for clarification, the only area I'm trying to keep humid is the taller section. Not the entire thing.
Why? Redfoots don't need a low humidity area. This will likely cause them to pyramid. Humid all over is the way to go, you just don't want a wet carapace all the time as they are prone to shellrot. A closed chamber allows you to maintain the needed humidity, but still maintain a dry surface in your enclosure.