Both teams are silver to plat.
The midlaner of team 1 is silver and picks a generic mage.
The midlaner of team 2 is plat and picks leblanc (or something else reliant on kills)
The midlaner of team 1 will probably get about 3 reports.
midlaner 1 loses vs plat leblanc and gets 3 reports - nothing happens. 
Irrelevant. There is no violation that would be verified by Riot's AI. **Losing in lane is not against the rules, and is not a reportable offense, let alone one that would be verified. ** Now all of the mid laners teammates being A-holes to him, that is against the rules and if mid laner 1 wanted to report them he certainly can.
it's not like any report is gonna do anything unless it is verbal abuse
ok
What you described has nothing to do with Tribunal. Unless you think report option = Tribunal for some odd reason.
The only thing reporting does is trigger reviews of behavior. If the only thing team 1 mid did was lose to LeBlanc nothing is going to come from it.
