Thanks, i did a bit of research and found an article where it states you can only get tokens in Summoner's Rift, but it was from 2016 so thought it might have changed.
I agree it makes no sense, i mean Twisted Treeline has ranked games, so why is it not viable to get tokens like that? Obviously if it has ranked games it is seen as a proper game mode unlike ARAM or any of the other event game modes which is basically just luck of the draw.
I mainly play TT with my wife and brother-in-law, so if one of us has a bad game we just write it off and move on, whereas in SR if i have a bad game i would ruin it for 4 other people :/