Can I report someone for trolling if they keep running into enemy fountain for suicide?
That
in my last game ulting into enemy fountain several times because "I am tilted".
That
in my last game ulting into enemy fountain several times because "I am tilted".
Yes.
Report them under intentional feeding.
Edit: Just looked at the match in question... He died one time in the enemy base. Not sure what you are trying to do here.
You can but it won't actually do anything as long as he isn't using chat. You'd have to send in a support ticket.