He will be the only one to resign.
Northam has more to lose by leaving. His wife wants him to stay. He’s a doctor with money and a career to return to once done. Dems have no leverage over him. What he did was stupid but not impeachable.
His calculation is to stay where he is — to hell with the party — and win back his reputation and name. He won’t resign in shame.
So Fairfax will go and the optics to black voter is, “White man gets accused of being racist. He stays. Black dude goes to jail.”
Everything you said is probably true. It’s also delicious for Republicans, sorry I can’t help gloating. The only way this works for the Dems is that the AG cannot get a promotion to Lt. Gov, Northam has to select a black man to be Lt. Governor once Fairfax is gone, someone who could be the heir apparent to the governorship.