The UFC honcho booked Kendrick Saturday for his son's 16th birthday party at the Brooklyn Bowl in Vegas. We're told about 300 people were in attendance ... but it really seemed like a straight up concert from the looks of this footage shot inside.

Kendrick is one of the hottest artists in the game right now, so getting him to play a show -- let alone a private one -- probably doesn't come easy. Yet, one way or another ... Dana sealed the deal.

Somewhere out there, Conor McGregor's hoping he can do the same with Floyd.