Could I get facial fillers and Botox before I go get minor surgery for an uneven lip line due to an accident?

Since the areas are enough apart, it is perfectly fine to do them before the surgery. I would alert the physician and anesthesiologist that this was done so appropriate measure are done to protect those areas.

Since the areas are totally away from each other it probably makes no difference. But you should contact the surgeon who is going to do the repair and get his input. It is always prudent to wait after a surgery to have procedures in the face