Hello mate, sorry to hear about your boxer
I had one in my GTI and I don't think you can fit the parcel shelf at the same time the guard is fitted. In fact I just had a look at the Travall site for the MK7 Golf and they specifically say that it cannot be done so that answers that.
The guards are good though. No rattles and a really oem look so I do recommend them. It just so happens that I have one for sale too! I only want £30 for it so if you do decide to go ahead, don't pay full whack for one. I have a Hatchbag boot liner in black too that also perfectly fits a MK7 Golf (£25!).
I still don't have enough posts to accept a PM (long time lurker!) but reply here and I'll pick up or check out gumtree, the liner and guard are on there.
Cheers