Seems like Joshua might shake loose, no?
It does seem plausible that he's a guy who they can't afford to keep. I think they'd certainly like to keep him, as he brings an element of size and physicality that the Canucks really need more of, not less. But if he's really looking to cash in on what could be a "career year" with his 18G on an unsustainable 21.5% shooting percentage...a big body who can score is going to garner some really stupid offers from a number of teams looking to beef up their roster.
He was really good for the Canucks last year, and is a solid PKer as well...but a lot of his success was really driven by his chemistry with Garland. More realistically, you're getting a ~10-12G bottom-6 banger. That's where we've seen teams make mistakes on these type of players at a high water mark "career year" like Jeannot trade, Josh Anderson, Marcus Foligno deal, etc. He's also already 28, so major term starts to get risky for that type of player. They can fall off a cliff in a hurry playing the game they way they do...and Joshua has never been the most effortless fleet of foot skater to begin with. There's not much room for his skating to fall off before he becomes pretty ineffective and relegated to chasing the play.
So if he'll sign for $3M or less, i think the Canucks would really like to find a way to keep him. But they've got a lot of other irons in the fire with Free Agency, including some bigger priorities. Especially if Joshua wants to start pressing up toward that Marcus Foligno, Josh Anderson type money in that $4-5.5M range. Anything like that is just a huge mistake in the making, for a guy who isn't a Top-6 Forward. Have to let him walk at that point.