Well first of all... after a chat with my new best friend :) ... (A guy I found locally that retro fits VW RNS510, DAB, etc etc) ... it sounds quite easy to retro fit the DAB aerial to the golf so I'll do a little write up with parts etc when I do it.
...but for now... I took the plastic casing off one of the FM aerial leads (the white one) and popped that into the DAB plug on the headunit and it works... sounds perfect.