Sorry, but it isn't that. If you click the "i" button then it gives you the info below. I actually cannot find the Lane Assist option but it should be there. I have gone through every package available and found nothing. The options you both linked to above are these options which are not Lane Assist but it could actually be incorporated given that there is no option for it.
Definition of Lane Assist: Gentle steering corrections: Audi active lane assist From a speed of 65 km/h (40.4 mph), Audi active lane assist helps to stay in the driving lane. If the Q2 approaches a lane marking detected by the video camera without indicating, the system intervenes gently in the steering to help the driver remain in the lane. Depending on the setting, this steering correction occurs relatively early or only just before crossing the marking.
If the driver chooses the first option, steering assistance is continuous. If Audi side assist is present, Audi active lane assist also considers traffic to the rear. If a vehicle approaching from the rear is in a critical zone, the steering intervention occurs when the turn signal is activated.
Audi Side Assist Aids the driver when changing lane. Audi Side Assist monitors the area behind your car using radar sensors located discreetly in the rear bumper. It then informs the driver with a visual warning signal in the door mirror if there is a vehicle in their blind spot or approaching quickly from behind. Works at speeds from approximately 10mph.
Cross-traffic assist rear Warns the driver of traffic crossing behind their own vehicle when starting to reverse without having a clear view of the situation (e.g. perpendicular parking space with restricted view or narrow driveway). The system alerts the driver first visually and then acoustically via the MMI, and can apply a brake jolt if a potential collision is detected.
My bad, I thought they were the one in the same. From what I've read Audi lane assist comes with small and medium sized cars that have hydraulic steering and active lane assist ( which I think is what you mention above ) can be added with electro magnetic steering. I can't find this as an option either. I think it depends on the type of steering fitted.