Yes, possibly if tgwbs did that, and Lommy was lynched, then Mac couldn't say anything to prove he's right. Though at the moment Mac was lynched as fake seer, we would know he was the Seer, and tgwbs would go as well. Though, there will still be one wolf left, and no seer, so who knows...
Only if we wouldn't conclude that Menel decided to give us two seers, which would speak for tgwbs and maybe he could make yet some mess...