Hi Lyndsey-
I haven”t fed wax worms to EABL nestlings,so I can’t speak to that(do offer mealworms). The only thing I can tell you is that the parents will come back to that baby in the morning. I had two that couldn’t take flight last year upon fledging & the parents came back & fed them all day long. My concern was that mine couldn’t get off the ground, which made them vulnerable to predators. It sounds like at least yours are off the ground. Hopefully, that little one can get in a comfortable position for the night.
Nicole