I don't want to say that your head technician is or is not competent, but if he compares to the BMW techs that I had dealt with... well...I would try on my own...
I don't know much about the Minis, but if you have the MK4 comp, there is a "service" menu... maybe there is a different way to get to it...

From the main menu, do you have "GPS Navigation", "Telephone", "Settings", On-Board Computer" entries? if you do, go to the one that says "settings" and select it. If it works out, you might be able to see in the top right corner of the screen a number, like 4-1/50 or something to that effect...

Can you do it in your system?...