Hi Dinoburb,
I had the same experience, with the exact same configuration: G90, MiniProSC, Rpi mobile. I did the same thing, trying to emulate Julian's setup. In the end it turned out the addition of the CAT cable (USB) between the G90 and the Rpi was necessary. I was pulling my hair out for about 2 weeks until I figured that out.
Good luck!
73's
David
AJ6RE