Best case scenario for the Ukrainian government is a partition of the country into West and East using the Dnieper river as a natural border. Kiev becomes Berlin 1946. Russia gets its buffer region. Western Ukraine joins NATO. But most importantly, while not ideal, the Ukrainian people can get on with their lives due to the political stability this brings.
Failing this outcome, Zelensky has to go one way or another. Ukraine isn't sovereign. People can pretend it is all they want, but it isn't. And it can only achieve political stability if it either joins NATO or meets Russia's need for security along its border. Since the Ukrainian government has failed to secure either of these things, the Ukrainian population now live in a warzone. And in response to this Zelensky has provided them with two things, and two things only: Weapons. Nationalism. In other words he provides them with death. If you are under 60 and male, you cannot legally opt out of this. For this reason, as strange as it may sound, if Zelensky refuses to relent, then ahhhh
Beyond Ukraine the security of the world rests on an acceptable outcome for Russia. Though intuition tells me all the details have been worked out behind the scenes already. Even still, things rarely play out down below as planned out up above.