Instead of an actual invasion, is this possibly the start of a revolt against Putin and his rule? Send help... Kill the help... Send more help... Kill that help and so on and so forth... Can Vlad fight on two fronts? Does he have enough fodder for cannons on the right and left of him?
He does have nukes.
That would be a long shot hope, that Putin can be destabilized.
Most likely he’d be replaced by a hard liner.
You’d like to see the army collapse and turn on the war. Highly unlikely, but Russia is a messed up country, as you saw with the Wagner revolt.