It will work if you want a paperweight...
GB for D2 updates more than the superficial files (non bootloader) that DX/D2 roms update. In fact GB for D2 also updates the radio baseband (completely separate from any romming). The reason the Romer doesn't work for the sensors is that D2G is different than the D2/DX, and everything that is updated by the GB build would basically brick your D2G, possibly to the point of not being able to sbf back.
P3Droid said that there's a GB in the oven for D2G, and that it'll be leaked by TBH as soon as it's ready.