Make sure her enclosure is as clean as possible to promote the healing of her tail, using paper towel substrate. I think you said in your other post that she is in a quarantine type enclosure which is good. You can dab the raw area with chlorhexadine/novalsan to clean it if you have some and then put a thin layer of triple antibiotic ointment (with no painkiller in it) over it once its dry.

Since being treated for parasites have you had another fecal done to confirm that she is now clean? If she still has some internal parasites that could cause her not to digest her food properly, so she may need a second round of treatment.

Wax worms however, do tend to look fairly undigested after they pass through the system. I'm not sure why that is, but I've noticed it when feeding them to several different types of geckos. An occassional undigested looking mealworm isn't cause for alarm, but overall they should look digested and not worm like in the feces. You might cut the heads off of the mealworms for now so that you know the nutritional insides are getting out when your leo eats them, but I'd recommend getting a fecal ASAP to make sure there are no remaining parasite issuse rather than using that as a long term solution.