Really depends on a lot of unknowns - hoe many troops do Wagner have right now, how many troops and of what quality Russia can put out asap if Wagner is really going after Moscow and how local Russian forces react and if they have the stomach to fight.
Keep in mind Ukraine can push as well to take advantage of the situation.
Wagner does not have a lot of troop. Also, remember Bakhmut bled them.
In any case, Wagner can't win against the russian military. Till now, they were operating with the assistance of the russian military. Plus, as Prigo has been saying for months, Shoigu has been starving them of ammo for a while.
Unless a big chunk of the russian army joins them, I don't see how they gonna succeed. You can't make a coup in a country like Russia with just merc alone. You need the military with you.