I have recently done some research on mk7 golf Diffusers (13 in total).

VW have made 13 different types of diffuser including side inserts (GTI model), all of which are interchangeable except 1...... the golf R.
VW would not tell me if the diffuser fit Tsi/GTD/GTI at all.

So my fellow Mk7 golfers does any of you know golf R diffuser part number: 5G6807568D9 "heckdiffus" (Yes, they have a personal name for it) will fit a non-R rear bar?