Bishop is a UFA, they are going to lose him for nothing.
If we pretend you didn't make a horrific mistake right off the bat, you are describing a situation that doesn't actually exist. For what you say to make sense, there must be an acute dropoff at a very specific place in the team's depth chart. We know that as we look at progressively worse players, the difference in ability shrinks to the point of interchangability. For a trade to be made, there must be another team with cap space, budget room, the desire to sacrifice the future for the present, and assets to move. There might be one team in that position.
Say your team has Player A and Player B, the most desirable and 2nd most desirable candidates on your roster from a Las Vegas perspective. You are going to lose one, so you have a choice
Player B
OR
Magic Beans you got from trading Player A
No GM is going to sacrifice the present success Player B represents today for the magic beans.
Before you say, "but what if Player C is the return instead of magic beans" consider this: If Player C > Player B, Player C goes to Vegas and you gain nothing by trading Player A. And in the event that Player C < Player B, you are worse off by trading Player A.
And no team is going to be trading good expansion exempt assets for an 8th forward or 4th defenseman, even if there wasn't an expansion draft those cheap contributors wouldn't be on the trade market except for big fish.