Just watched your video.
I'm pretty sure that is not a spray clutch issue.
You'd head a dreadful mechanical noise .
To me it could very well be a fueling issue, you can hear the bike almost wanting to start .
Yes it does seem a bit slow turning over that could be anything from the battery being too low an ampage , battery cables need upgrading or the starter motor needs a service or replacing.
It could be something else but I'd look at the battery /starting circuit first.
Well done on rescuing another Benelli !!