14 day Ban for "Griefing and Trolling"

So, I just received a 14 day ban for Griefing and trolling. The game in question is linked. Actual ban message: https://i.imgur.com/gSXCbnY.png

And so, the background of what happened is this: (I told the rioters in my ticket to check the champ select logs and ingame chat logs to see that I am not lying)

For context I am queueing solo and the other 4 ppl are a premade. I got into a game, I ban lee sin quite a lot, but I was alt tabbed watching worlds, then I hear its the last seconds before ban phase is over, so i quickly ban Lee sin, but as im pressing it, I saw the teammate had lee selected so i tried to swap to xayah(another champ i ban frequently) Then ofc, the guy who wantd to play lee sin(Rammus in the game) goes off about me banning his lee. Then his premades start locking in the following: Teemo, Nunu, Singed, Rammus, all with cleanse ghost.

I am last pick. I really didnt want to dodge, so I decided id play along and have a bit of fun with these guys, since why not? So i lock in tryndamere with ghost cleanse as last pick.

Then the game goes on as it does, everyone trolls around, and though the premade tries to tell the enemy team that Im a griefer, I tell them concisely that my 4man premade teammates were angry I banned one of their friends' champions by accident and decided to troll long before myself.

Game ends, nobody is really toxic, everyones just joking around.

Fast forward to today.

I received a 14 day ban. Who am i griefing? Who am i trolling? Is accidentally banning someones' hover'd champion a bannable offense?

If anyone can give insight on this, as I wait on my ticket, I would love some.

Heres also a ss of the rammus (who wanted to play leesin) and his 4 man premade. https://i.imgur.com/uHbw58S.png