So, you’ve got a GS911. It’s given you a fault. When you clear this down, the bike still won’t start. Is the same fault back? If so… then it’s no surprise the stater won’t spin as the starter relay is isolated by that virtual fuse.
It’s therefore. one or more of things covered by that fault code. Clear the code again. Switch ignition on. Does the code come back immediately? If it is back, the immobiliser ring antenna thing looks likely although I’m not sure what the Ecu checks when the ignition is turned on. Anyone?? Once we know that then we have isolated one or more cause from the list linked to the fault code.
If not back, then it is probably going to come back when you press the starter button. Now you know it’s linked to the bike trying to start so start - relat, coils injector.
I think you said you’ve investigated the coils, but all seems ok.
Starter relay. No idea where it is, but find it & check the wires and connectors. Replace if it’s a standard type relay.
Injectors don’t seem to have been mentioned. I don’t know, ummm Pull one, bang 12v down and see if it comes to life
Immobiliser/ ring antenna. I think someone this only activates when the ignition is switched on so it shouldn’t cause the bike to cut out once running.
Tank off isn’t really a big deal, just loads of fasteners and panels. A bit awkward if it’s full mind.
Good luck.
I take it you have properly checked the side stand switch, the clutch switch and the kill switch.