I wouldn't trust Halak right now and he has long history of being very streaky and inconsistent. Too much so to be a true #1 goaltender. He's amazing when he's on, but when he's off it makes you wonder how he still has an NHL job and he wavers from one extreme to the other far too much for my liking.
If I'm Winnipeg, I kick the tires on another goaltender, especially if you're going to expose him in the expansion draft. There's just about no point to doing this deal at that point.
I'd also honestly rather have Stafford, he's a versatile top-9 player and a decent skater. Not really a fan of Lee, but can work well on the power play. Too slow of a skater in my opinion for a team like Winnipeg that's looking to go in the more uptempo direction.