If you have an OBi2xx and an OBi1xx, the OBi2xx will always receive GV inbound calls. You need to fork the call from the OBi2xx over the OBiTalk network to the OBi1xx. Assuming GV is defined on SP1 make the following changes using OBi Expert.
OBi2xx:
Voice Services -> SP1 Service -> X_InboundCallRoute: ph,pp(xxxxxxxxx)
Replace xxxxxxxxx with the OBi number of the OBi1xx
OBi1xx:
Voice Services -> OBiTalk Service -> InboundCallRoute: ph
You only need the OBi1xx change when the call is routed to the Auto Attendant.
If you have two OBi1xx's, the last OBi1xx to register to GV will receive inbound calls. Make the above change to both OBi1xx's. Now it doesn't matter which OBi1xx receives calls.