That most certainly sounds like Jeremy at the end; multiple fan blogs have the song listed as featuring him, and I admit I've assumed part of the appeal of doing a record release show together was for them to play the song together live. I only have a digital copy of the album thus far so I can't look at the album's liner notes to say for sure, so I'll assume you know more than me, but a good portion of the internet is under the impression that that's Jeremy screaming at the end there.
Also, Will Yip has done good work, i.e. Floral Green, Magnolia, the new Blacklisted stuff, but I can't forgive the latter half of Youth or how Feast of Love is so repetitive and devoid of the hooks that made love Pity Sex to begin with.
A quick search pulled this up, for one.
If you blame Will Yip for making those bands change their sounds then you have no idea what you are talking about. Both Citizen and Pity Sex have said that they made the albums they wanted to make with Will. He doesn't force bands to change their sounds and that's ridiculous to suggest.