I have two of those glass 3 shelf display humidors.
I tore one completely apart and sealed it up because I could read a newspaper through the cracks.
Prior to fixing the one, which I've still never used since I fixed it, I ran a humidifier in each one and had 3 pounds of beads built into the back of the display shelf I built.
Guys, help me with the name of those little electric humidifiers, will ya?
Oasis, maybe? But I had the blue ones from CI in there.
Point being, don't sweat it, brother.
That's a paper thin spanish cedar veneer. The shelves are the only thing you're really seasoning, and there's really not enough wood in them to worry too hard.
They'll take up a couple drops of water, max.
I hope it works out for you a lot better than they did me. Sincerely.
If you have troubles, just ask for help!!!