I think one of them did. I forget who. that's all I need.
Let's see:
Jeff - Didn't like it from the start, clearly on record as not finishing it (Bombcast)
Brad - On record as not finishing it (Bombcast)
Drew - Didn't play it (Assumption)
Rorie - On record as not liking Witcher and not having played it (Bombcast)
Vinny - On record as not having finished it (Beastcast)
Alex - On record as not having played it (Beastcast)
Austin - On record as not having finished it (Beastcast)
That leaves only Jason, and as I recall he's on record as having stopped in the middle as well.
Just listen to the latest Bombcast and Beastcast and it's clear that nobody has finished it (or come close).