Well I guess it's to late for this method, since they already drilled your front bumper, But a friend of mine did this on his Lexus and it's awesome.
Buy about 12 rare earth magnets (3/4" - 1")
Epoxy 6 of them to the inside of your bumper
Epoxy the other 6 onto the back side of your license plate
Get a good quality microfiber cloth
Spray glue the microfiber cloth and the backside of your license plate (right over the magnets)
Stick the microfiber cloth to the licence plate
Trim the cloths around the edge of the license plate
Have a plate when you need it, No plate when taking pictures, No drilling!