It might help to know, and for him to know, that this is extremely common. Thanksgiving break is a time when many new students articulate a desire to leave or transfer. By spring they are often happier. (I have been through this with 3 kids…) In some ways it doesn’t matter what he does as long as he is getting out, because that is a start, and it could be on or off campus.
Some schools have support groups for kids who are feeling lonely, hopefully disguised in some way so that it isn’t embarrassing 
Has he gone to the counseling center for advice?