McFadden in a trade. Need help!

Ok so I️ posted a trade earlier but it’s evolving. I’m in a full pt ppr 14 team league.

QB: Tyrod and Mariota
WRs: Julio, Decker, Agholor
RBs: Murray Ingram Ellington Stewart
TE: Graham and Doyle

So this guy wants Mariota and Doyle and Will give me Steling Shepherd and McFadden. Have started Mariota all season but just picked up Tyrod. Zeke is playing this week so McFadden won’t help and it’s anyones guess what will happen when zeke is out. I’m thinking of offering the same two guys for Shepherd and Kenyan Drake. Not sure who will have more upside Drake or McFadden. I️ don’t really see getting any value for Mariota otherwise. Let me know what you think. Thanks!