If the Leafs want to replace Freddie right now with any goalie that's making anything above the league minimum than the other team has to be willing to take him back, or a third team would have to be involved.
So if Dubas finds a partner in the Kings (and they may be one of the only teams this can work with) than the upside is the Leafs get an aging but playoff-tested keeper and although Toronto will likely have to give up something for the Kings to help them out, is the alternative to stick with Freddie, who has clearly lost the confidence of the team and face the very real potential of another early playoff exit? The city will implode if they don't make it out of the North.
As for what happens after the season, if Dubas can convince Seattle to take Quick in the expansion draft - with a sweetener I'm sure - there goes the cap concerns of his contract.
So the question is, just playing along in case this rumor has teeth, is Dubas ready to give up something (pick(s)/prospect) to, arguably, upgrade to Quick for a run this year, then possibly give a little more to Seattle to shed his contract this Summer? Huge risk with huge upside but look at it this way, if Dubas gives up assets to bring Quick in and the team fails, he's likely gone. But if he sticks with Andersen and they fail, he's just as likely gone.