Something came up in a link from that article that I had not considered. I was reasonably confident Hamilton would not 'walk' without another title, just to set the record, but I had not considered him 'taking a sabbatical' as they put it. The more I consider this, the better option from his point and Merc point I see it being.
There would not be a direct conflict of new Russell v established Hamilton.
Hamilton would not have to break in a new car, He could consider his feelings on not driving but without having burned his bridge back next year if he reconsiders.
Merc would be looking for a single year replacement so drivers like Vettel become a viable option. They could even run the sim driver for a year, or part of a year to better establish the setup comparison. They need not consider long term.
After the year, there may be other options on the driver market, or Hamilton could come back.
When arguing with a fool, be sure the other person is not doing the same thing.