At least he is someone with something resembling medical training, which is some big potential to help, since harry wasn't even clear on how to use a first aid kit.

At first I thought that Harry just sitting there was counter-productive, but then I remembered they probably wouldn't let him kidnap muggles even for a night. However his father would be brought in promptly if Harry asked that.

Also I tried to do some fact checking while typing this, but it turns out new chapters had come out (so I'll drop this and go read them instead).