I can confirm that this works. I had the active driving assistant before so I didn't need to enable that but I did enable the lane change assistant. For anyone else looking to do it, here are the relevant codings to enable the lane change assistant, these are copied directly from the video:
BDC_Body3 > CAFD_7083 > SPURWECHSEL_ASSISTENT
Default: nicht_activ
Change to: activ
HU_MGU > CAFD_3E52 > SPURWECHSELASSISTENT
Default: nicht_activ
Change to: gen_1
SAS2 > CAFD_42C1 > C_SWA_VORHANDEN
Default: Nr000_nicht_vorhanden
Change to: NR001_VORHANDEN
Here is a picture of it working, it does a cool little animation that shows the lane expanding and then the 'locked car' brackets move over to the car in the destination lane. I took the picture right before the brackets moved over, the HUD also shows a little green arrow in the direction of the lane change.. its awesome! Thanks for posting this OP.