RCM isn't a problem, don't bother programming it and if it is ad you can't anyway, ae probably can but only to reinstate it because you accidentally reprogrammed it in the first place Lol. they aren't something that you need to program.
Don't send anything back to China because you won't see it again, postal system is corrupt.
If you can do everything other than RCM then be happy with it trust me.
RCM are plug and play so no coding needed, 10-30 pounds for another from the breakers and likely they'll be going down in price because nobody ever needs them except silly ppl who got a vcm and accidentally reprogrammed them to twin airbags!
(plus the mk7 it'd getting a bit old and trampy now so even less demand)
New RCM plug in and works.
Any other faults with wiring or resistance has nothing to do with the module so no need for ids.
In stead, sit on the back step or a park bench and breathe in the fresh air and enjoy the birds as they dance through the trees......