Leafs fan coming in peace. Jack Campbell is a wonderful person, and I know it's hard to believe right now, is a very talented goalie. However, he struggles badly with mental health, something that's been a known since his days with LA. He's had his good moments, and he's been good then, but he's had some incredibly down moments... like now. Mental Health struggles are a terrible thing, but I can only imagine trying to deal with it, as a NHL goalie, in that spotlight.
What would be best for him, and your team, is for him to enter NHL Player assistance, and try and put his mental health back together. It would allow for him to be put on LTIR as well.
I don't know that he'll ever have the capability to deal with the pressures of being a NHL goalie, but with that contract, you do everything you can, to try and help the person, player and team.