The 46 MAY be too big for her, but I have mine in a 55 gallon and she is doing fine it just depends on the snake. I would ditch at least one of the lamps and get a UTH sized for you tank, those heat lamps kill humidity very quickly.
Personally I use Cypress mulch for bedding and it holds humidity pretty well, another substrate you could use is Eco Earth (shredded coconut hulls) it holds humidity even better than Cypress.
I don't use aluminum foil on top of my tank I use hand towels that I get nice and damp (not soaked) and put those on top of the tank and it works very well. I have heard good things about the foggers and feel free to get one and try it out, just keep in mind that they will lower your temps when they are on.
I would try switching the substrate and getting a UTH and that should help alot.