Doom Bots Level 100 Victory Icon?

I just thought about it, did Riot ever even confirm this? I can't seem to find them saying this was true anywhere. Can someone show me proof that it's not a myth? The reason I thought it was true in the first place was because someone linked me to a "Doom Bots Tier List" website that says it's true, but that site is 3rd party. When I say proof, I mean Riot Games actually mentioning it themselves.