Not really. The goal is "find the grain peddler" with the side goal of "determine if he's a traitor" (or find evidence of it). Both are achieved regardless of the twist: The peddler is found on a successful Scout check but also found (dead) with the snake twist. After all, Scout doesn't determine state of existence, only finding something/someone.

That happens, succeed or fail.
What the twists/conditions do is make it harder to succeed overall by beating down the guardmice over the course of the GM Turn.