My friend,
Do I understand that your belief is there are more options than WWIII or negotiated peace? I would be interested in understanding what you think those options there are. I can think of two other options that I don't believe to be likely outcomes 1) sustained and perpetual violence along the Ukrainian/Russian boarder or 2) a victory of one side over the the other.
If negotiated peace is not to be considered a likely outcome, then escalated violence to secure a victory remains the only likely solution to my way of understanding. That is what I call WWIII. The grind of perpetual violence is no substitute for victory in the rhetoric of powerful people, and they will not be stymied by dark beliefs of probable outcomes. Help me understand other ways to see this.