Matt Murray for Jack Campbell.

The Leafs haven't had a trustworthy back-up goaltender to Frederik Andersen since... Curtis McElhinney, of all people, left town. The dude's consistently played in >70% of the team's games since he got there, and I wouldn't be surprised if it's started to wear on him. They need a competent back-up to be able to fill in for games where Andersen can't play. Jack Campbell might be it, but I don't think anybody's that sold on the idea.

The Penguins are cutting salary and generally can't afford to pay both Murray and Tristan Jarry what they're worth. Sure, Murray's had a bad couple of seasons, but he also won 2 Stanley Cups as a rookie, and we saw the kind of leverage that got Cam Ward throughout his career in contract negotiations. The Penguins don't really have that kind of money to toss around at the moment. The consensus seems to be that everyone thinks Murray is the one leaving town at the moment, so the next question is, of course, where does he land?

Now, why would the Penguins want Jack Campbell (outside of the obvious "there's only room for 2 goalies on a roster")? A fairly easy answer: cost certainty. He's signed for 2 more years, and it's all base salary with no bonuses. The Penguins don't have to spend time in RFA negotiations with Campbell like they would with Murray and Jarry, and he'll ultimately be cheaper than whatever money they'd have to pay Murray.

Why would the Leafs want Matt Murray? A not-so-obvious answer. He's been kinda bad for the last couple of seasons, as previously mentioned, and, by bad, I mean bad.
But! He's clearly been good before, good enough to win 2 Stanley Cups (and also AHL Rookie of the Year, Goalie of the Year, as well as breaking the AHL shutout streak record).
And, of course, where did Matt Murray play junior hockey? With the Sault. Ste. Marie (now just Soo) Greyhounds. From 2011 to 2014. When Kyle Dubas and Sheldon Keefe were, respectively, the GM and head coach of the Greyhounds.

If there's anybody that knows Murray well enough to maybe help him get back to how good he used to be as a goaltender, it's Dubas and Keefe. And they might know something that we don't, enough for them to take a roll of the dice on it.

Murray despite his horrible season still has more value than Campbell. 2 time Stanley cup champion. Murray is probs getting traded for a 1st.

As for Campbell. Leaf fans love him. The guy is super nice, has enormous potential and could become another Markstrom. Just gotta wait and see.

touché. again, i'm just a bum on the internet and have zero idea as to how contract negotiations are going to pan out.

also apparently the penguins did offer Murray for Kapenan in a 1 for 1 but according to Friedman "the draw back was his rich arbitration rights" basically while people are saying 4-5 mill with Arbitration he may be going for 7mill

can't afford him

It's an interesting proposal but I bet the Penguins are looking for a higher return on Murray, and even more so someone whose not a goaltender.

Makes the Leafs goaltending situation a little more complicated too. I think if they get Murray they move Andersen. They're finances wouldn't allow them to have two goaltenders in the 4-5 million range.

I don't think Campbell is the guy Leafs would move to get Murray despite all the connections the OP posted. As already mentioned, Campbell is a fan favorite and really the Leafs only just acquired him this past season. Way too soon to move on from him.

For the record, I don't think Murray is a good option for Toronto. The injury history should be the thing that scares Dubas and frankly put, what happens if Murray gets injured? That means Campbell starts most of the games which is not the issue but it is when Campbell needs rest and a backup needs to provide adequate goaltending.

Huge no as far as I'm concerned regarding Murray.

I'd be concerned about acquiring Murray - especially if the Pens (who won 2 cups with him and gave up Fleury to keep him less than 3 years ago) are prepared to give up on him now. That's a Red Flag. Not a deal breaker but clearly a note of caution.

At the same time, given the cost of acquiring Murray, wouldn't it make more sense to instead put those trade assets towards acquiring Korpisalo? A lot of analysts suggest that he may be available from CBJ.

As between Murray and Korpisalo? There's a lot of recency bias here, to be sure, but I don't think the guy who stopped more shots in a playoff game than any other goaltender in the history of the National Hockey League is a fluke. On a heater? Most def. But a fluke? No. That guy clearly has the talent to win a cup. A goalie like that in the playoffs? That's the guy I want to take a gamble on.

If you are going to make a bet, I'd rather bet on Korpisalo being "that guy soon" than Murray bouncing back to being "that guy again". Especially when the cost of acquiring and paying Korpisalo is less than Murray.

At the same time, could either of them be Andrew Raycroft? YES. We need to accept that may be so, especially under the brightest lights in the NHL. It IS a high stakes gamble.