So—I take it that your opinion is that any votes alleged to be lost by one candidate due to the presence of an unqualified rival on the ballot would be hypothetical or conjectural? If so, chance of winning would have nothing to do with it.
When the candidate in question is on the ballots in so few states that even if he had won them all he would still have had less than half the necessary electoral votes then yes, any damage is indeed hypothetical or entirely speculative. If the candidate was John McCain, however, then that would be an entirely different matter. As the judge in the Hollander v. McCain seemed to indicate when he dismissed that suit.