A G3X Touch and non-touch GDU cannot be used on the same CAN bus, there are incompatibilities between the two that prevent us from integrating the two on the same system.
This is what I have in my RV-9A. I have the GDU-475 on the pilot side and have the GDU-370 on the co-pilot side. The GDU-370 uses its own GSU-25 ADAHRS and GMU 11 magnetometer and a GTP 59 OAT Probe. This gives me a fully independent display.