Hey man.

Wauw, poor little guy! <3 I know how you feel - petshop amphibians and reptiles are often very badly taken care of and suffer in their various ways (at least here in DK). Good on him that he ended up with a guy who had experience in handling this.

Hope all turns well for him If it isn't known to you already, gutfed, healthy nightcrawlers are often a very good, nutritious and "soft" feeder, excellent for helping a metabolism back up and full of nutrition, if they've been missing that for a while (at least to my knowledge reg. terrestrial toads)