Luca.... appears you are heading the right direction.... good for you....
I can't imagine the stator cooking already, but I've heard weirder stories.
Test that stator at idle, at the connector to the voltage regulator. Stick your volt meter in any 2 slots..... switch over to AC. You can test at idle and at speed (2000 rpms will do it). If I remember right it should be reading 50 volts AC or more. Test all 3 slots. And these numbers should be fairly steady.... no leaping around. Bouncing ok, leaping not so much.
Hopefully your test is good. If not, its looking like its the stator. It looks like you know how to do this already? If you do this, take a very good look at the leg off the stator, and see if it was rubbing on the mag wheel (It happens right there). I've always have had issues with that silly wire clamp that is supposed to hold it away from the wheel. So much so I had a buddy make me one much more stout, and fail proof.
Stator tested good? Go to the battery and switch to DC. At idle and lite flickering, it should read in the 13+ volts range at idle. Is it bouncing around drastically? I'd suspect the volt regulator, but I'd also be looking at all the wiring from the regulator to the battery (not a simple task).
Inside the loom that runs under the X, are 2 red (If I remember correctly) wires exposed to anything you could have hit. Ask me how I know. We get the occasional windrow of gravel at different points on our roads, shoulders on curves. Thats what knarled my wires to almost broken. I was getting sketchy readings at the battery, and replaced regulator. I found them, and was very surprised I was getting any charge at all. My regulator was fine.
Sorry about guessing on 2 items, but my shop book and schematic are both outside in my shop. ...
Need more help.... ? Hollar!!
Bruce