They were never going to be able to keep all four anyways. Especially now that Matthews has been on an absolute tear and looks like he could end up with more than JT got.
Marner should be close to $9 million too.
It's an interesting situation to watch. And while this sort of thing will happen with any fanbase, always amusing to watch the sheer devotion some Leaf fans will go through anytime someone talks about having to trade Nylander.
It could work out but it's just a matter of timing. While they're currently playing with Marner and Matthews being RFA's at the end of the season you have to think negotiations with them or ongoing and they could see extensions in the new year, so really it's like Dubas is negotiating with all 3 at the same time. The tricky part is next season they only have space to pay two of them, a third has to take a bridge contract. Then when Marleau's contract expires in 2020, they can afford to pay #3.
To make that work everyone needs to be willing to buy into it, and so far it doesn't look like Nylander is willing. They're considered a 'trio', but one is going to be asked to be paid significantly less for a year or two, and so far Nylander is saying not me. They may just have to trade him, and they're certainly strong enough up front to do so.