Just happened today.
I flipped a red joker doing 9 dmg with a Marshal blade strike to Seamus, making it was the third time I had him down to 1 Wd. Last model I can activate is a summoned Stalker in CC with Seamus. I have a decent hand left and I am thinking all I have to do is hit him and he is gone. I flip the black joker for my attack and Seamus once again survives a round with 1 Wd.