I had a very similar accident in the exact spot and even though it was in a parking lot, the other party's car tore 3 tabs. Judging by your last picture, you might be better off with a new rear bumper since there might be tab(s) torn as well. Ultimately, if you pay for insurance, use it.
Originally Posted by E90_boostjunky
correct, unless you buy a 335i mtech rear bumper it should come with a diffuser, if not then you will need to buy both.
335 or not, if you buy a new bumper from a vendor it'll come with a diffuser unless for some odd reason it's stated otherwise.