I'll further add that in 5v5, the Sabres score more with Skinner on the ice than any other player (outside of JQ's 17 games) and Skinner's GA/60 is middle-off-the-team, better than Jordan Greenway's.
There's not going to be a buyout, Sabres can't afford the cap hit and it doesn't make any sense with a productive player. Soonest exit would be to a playoff team in trade, maybe with salary retention, but good luck doing a one-for-one shipping Skinner out in order to land what the Sabres need... a scoring forward? Sabres aren't desiring to take a package in return unless they're desperate to get him out.
I assume the usual asset management techniques apply and if the Sabres don't want Skinner, they move him the summer before his last contract year, which would be 2026, presuming he waives his NMC. He may decline to move, and then it's the same situation as a rental at the trade deadline in 2027.