Honestly, when I place my team on the board, I like the look on my opponents face when they see what I'm playing and they figure out exactly how I am going to beat them. Vermin is a much too subtle figure for me. Though it might be fun to team him with Nightshade and Floronic Man.
I am not removing this until we get the rest of the Marauders, Cameron Hodge and Genoshan Magistrates.
I recall lengthy discussions about the subtlety of the 'beginning of turn' wording prior to the ruling that Lancelot has affirmed. Perhaps it is apropos to take your question to the rules forum and catch the attention of an orange. Though I vaguely recall a situation like the one you describe being verboten, it seems plausible.
Okay, well I never did plop this over in the rules forum, but I just got back from reading the GSX vs WoS Healing Trait for Wolverine, and it was pointed out that:
"When a player begins his or her turn, first resolve and end all effects that last "until the beginning of your turn" or "until your next turn"’, then resolve all effects that occur "at the beginning of your turn". (Rulebook, p. 7)
So, I was wrong with the way I said it, but I was right in that the effect that you are trying to achieve (Poison followed by removing the Smoke Cloud tokens) is disallowed (has to be remove the Smoke Cloud tokens followed by Poison).