Taking one for the team and dodging

Alright my doods so here's the thing, in a very few amount of ranked games I've played I've had people who obviously troll from minute one. For instance, just a few minutes ago during champ select for a ranked game the person who was assigned support first picked Yi and then asked in a very trolly way if he was a good support. When the team responded with something along the lines of "Oh god please no." he switched to Zed. He also refused to drop smite from his summs. While it was my turn to lock he switched over to Karthus and said that he'd carry, at which point I took the initiative and dodged, resulting in a leave buster penalty. While I believe that the leave buster can help discourage dodging for bad reasons like getting autofilled, I think there should be a way to report someone trolling and leaving the lobby without incurring a leavebuster so you can prevent a circumstance with blatant trolling such as this, especially in ranked. For instance, a way to contest the claim and subsequently have a system or employee look over the conversation history to search for trolling, while this obviously isn't perfect, I'd be extremely interested in a way to avoid getting dragged down by trolls without being punished for it.

Tldr; There needs to be a way to leave champ select if someone is actually trolling to salage lp.