I think we're using conflicting info to assess the
parents actions. In some scenarios they seem possibly overprotective- i.e. possibly looking to track his whereabouts. However, they did not panic until he didn't show up to the dentist, which to me seems pretty normal for a college sophomore who may have been out with friends, doing his own thing and not causing worry.
I will also say that when I was 19 I almost always went to the dentist with a relative because I hated it and, of course, they were paying
I truly hope Blaze is ok.