Leave the hole, grab two big washers, a toe hook and a nut, put that shit on and be m4d JDM y0! 
UPDATE:
she really needs to get an allignment bad and wants to take it to the stealership (since it’s covered under warranty). This will be the 3rd time she has has to take it back to the stealership in the 2 months that she’s owned the car. I dont know much about the Lemon Law, but if it does come into effect, can they deny her because of the hole in the bumper? She would leave it for now if that wont effect that or anything else at the stealership. What do you guys recommend?