Trolls who are "technically" NOT trolling.

So I just had a ranked match totally ruined by a Trundle who was top lane and he just left top completely, perma stayed bot and farmed my jungle and was definitely not "feeding" but he basically ruined the game for all of us since we had no top laners anymore and Nasus just farmed and destroyed top of course. So even tho he was "1/4" he still completely ruined our game. Is this method of trolling detectable by the system? Because stuff like this is basically the same thing! I need a Riot employee reply for this issue! Trundle was far under leveled compared to enemy top lane. Proof is in my match history, i wont be naming and shaming this person as that is against the rules.
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