I know things... A lot of things.
Join Date: Feb 2015
Motorcycle: GSXR 750 K4
Re: R/R and Stator look fine, but bike died
If you charge your battery externally, you should be able to disconnect your R/R and stator from the electrics of the bike and take them out of the picture for the time being. If then you still don't get any priming and the starter doesn't operate, you'll have to check the interlock system. Search the site for terms like "ignition interlock test CHEC sidestand starter", as there's plenty of advice there already. A dead ECU is certainly a possibility given the history of the issue, but since the starter isn't operating either, something might have failed which prevents the ECU from being powered. Suspects include the starter button (due to overheating from the overvoltage), the sidestand relay and other components of the interlock.
Once you get your engine to run and repair any damage that might have been caused by the overvoltage, you can test the charging system components and replace as necessary.