This is an interesting connection, one with a lot to consider. For starters where DCL's value is removed Newcastle as a suitor. Also on if part of their interest is to buy off teams that could be a possible table threat.
That said if Dom's value is relatively comparable to last years, he's overvalued. Add a suitor with limitless funds and the recipe to extract a premium return, the transfer is possibly the grounds for astute business by us. Not without the possibility to also screw the Magpies in FFP if they pay an inflated price considering the wage boost he will get. I fail to see him grow his value in a reasonable way where they would make profit on a sell on considering also his new wages. That isnt a huge rationale for Everton but an interesting caveat nonetheless.
The short of it is though, if he is going to move in the next 2 years will his value appreciate, and is this the best context to extract premium value. There is a strong case to saying it could be.