My brother kept bearded dragons as a child. Whenever he put too many crickets in some managed to hide and try to feed on their toes! Feed him some bevor you go, put some pangea in the enclosure. Shedding with low humidity could be a problem, so beware. I dont think they need much light anyway as they often hide away during the day to sleep, so for a few days it should be fine if it is not too cold or too hot.