A6 Allroad side assist fault - J770 slave (4G0907568E)

[Allroadaudi]

Hi 

I have a 2014 A6 Allroad 3.0 TDI 204hp with ACC and side assist. The side assist slave module (J770) has stopped working, with the effect that the ACC becomes unavailable as well. 
 

It seems that the OEM replacement part is hard to come by - 4G0907568 E - and my question is if anyone has any experience with a different part number working as a replacement. I can see that some sites are claiming that 4G0907568 M will fit my vehicle, but my dealership of course says that it won’t. 

I would greatly appreciate any tips or input, as I’m trying to get around having to buy a new way too expensive part from Audi.