Thank you for the responses!
Marcel uses a ceramic dish, not a bottle (I really did take all the precautions I knew of to keep this from happening)
I had to switch his food after his vet visit, and he doesn't seem thrilled so far, so it's likely that that's the reason he isn't eating very much because he is not interested in the moist food either (long story short he has 88g to lose as well as his infection to contend with because of the food I was feeding him. But the vet said his teeth looked good, so it had to have happened between last Saturday and when I noticed it the other day)
Anyway, I guess it's a mystery, but I'll try moistening his new food to see if I can entice him. I've kind of been going by the "if he gets hungry enough he'll eat it" mentality, but is there a time limit I should put on that before I do something else?
BTW, the new food is Mazuri's Insectivore Diet as prescribed by the small/exotic animal vet.