He didn’t stop to check his vehicle. When you hit a deer, which happens occasionally, you always stop, check the front (which should hair stuck on it), pop the hood, inspect the engine to ensure that no belts have been thrown, then (assuming you have cell service) call 911 and get the number for the DNR.
I assure you this guy knew he didn’t hit a deer. I’ve hit a deer head-on before. That vehicle was not drivable after. There is very specific damage when you hit a deer. Also, a person does not look like a deer in any way in case you’re curious.