I have 2018 Scab that I rarely haul anything in. I just noticed that there is a hole on the inside of the tailgate. It's just off center to the left (driver's side) and high on the gate. It's about the size of the end of your little finger or just a little smaller than a dime. Should there be a plug there? Why is it there in the first place? To adjust the back up camera? Anyone have an idea?