3 year old grey/black tooth

My little dude bumped his mouth on our dinning room table. A week later his tooth turned grey and now almost black. I brought him to a Pediatric dentist but it wasn't a good one and I didn't like them. They told me it will fall out sometime between 5 and 6 and to do nothing unless he gets a abscess. This seems so bizarre to me to wait this long for it to fall out.

Our insurance is really terrible and it was really hard to find a place that would accept us. But this place didn't seem legit and was sketchy. Has anyone else experienced something like this?