sometimes a little does get left behind - you can actually just see a patch between Trevor's eyes and this picture is labeled 'just shed' -
bathing and a soft toothbrush are worth a try
it may also be that he's going straight into his next shed - there was a point where Trevor was shedding almost continuously as he was growing so fast, he still sheds each part of his body in a sort of sequence, always starting with his head, so he would complete his full shed and his head would be starting again
vet's are expensive, parents tend to be wary of unnecessary expense, especially at the moment with banks and mortgages still a bit shaky after the credit crunch, so they will want to be sure he really needs a vet before they agree to it.
He shouldn't have a hide - beardies need to stay in the
uvb light all the time to avoid getting mbd (you can see Trevor's right front foot is bent, that's from mbd from before I got him, the bones were damaged and couldn't support his weight; he still walks on that wrist although he uses his left foot properly now)