Adams shouldn't be angling for a higher end defender like Chychrun. Add in a younger kid like Fabbro, who has proved he can play top 4 minutes well in Nashville, and that'd be enough to improve the defense.
Take the Olofsson, Fitzgerald and pick for Fabbro and Sissons trade. It's not the big Chychrun trade, but look where that puts the Sabres:
Skinner - Thompson - Tuch
Quinn - Cozens - Peterka
Mittelstadt - Jost - Asplund
Girgensons - Sissons - Okposo
x Krebs, Hinostroza
Samuelsson - Dahlin
Power - Fabbro
Bryson - Jokiharju
Pilut - Lyubushkin
(Substituts Clague for Bryson or Pilut if so inclined)
Legit bottom 6 which would be hard to play against, with some really good defensive depth. This is the type of move which put the Sabres in better playoff position.