The problem is Buffalo could come away with 2 CB’s or 2 WR’s in the draft. If that’s the case, you don’t really have a spot for either Douglas or Cooper.
We know Buffalo will come away with 1 CB, and that Dane Jackson is the veteran backup. I definitely wouldn’t mind Jackson or Douglas as the CB3 and CB4. It could just come down to money - how much do you want to pay a CB4?