I agree with Mitch. If you hang it, and there are ANY issues, it will be on you. If you have an earthquake and that TV falls, they'll expect you to replace it. If someone does a pull-up on it, and it falls, they'll expect you to replace it.
I would like to require them to hire a professional to do it, since there would be no liability for me. Practically, I would probably just let them do it though. I've never been that worried about a few minor drywall patches, but you could easily let them know it'll be $25 or $30 or something off their deposit when they move out.
I prefer not to let tenants "return the property to original condition" after I had a tenant fill several gouges in drywall with toothpaste.