A new ECU is £712


I think your R runs a 1.6 ecu?? If it does then you should be able to use one from a BP or ST etc. Just change your eprom over. The SPS is definately different, as is the 998, S4 and the new stuff.
It sounds like your mate has done the tests and knows what he's doing, but checking "continuity" through the sensors won't necessarily prove they are working. Many of them need checking for resistance etc.
Possibly be a play on the wording but may be worth double checking?