As Charap and Radchenko show, the reality is a bit more complicated. Johnson didn’t directly sabotage a ceasefire deal in spring 2022; indeed, there was no deal ready to be signed between Russia and Ukraine. The two sides hadn’t agreed on territorial issues, or on levels of military armaments permitted after the war. Ukraine’s position during the negotiations necessitated security guarantees that western states were hesitant to provide. And there were domestic political questions inside Ukraine related to Russian demands about “denazification” to contend with.
So no, they hadnt agreed to revert to the feb-22 borders, that was still a matter of contension, and Russia were pushing for Ukrainian disarmament post war (i.e. surrender).
My dispute wasnt that there were attempts at negotiation, obviously there were; Macron in particular made a big show of pushing for them. But the idea that Russia ever offered status-quo ante-bellum (as they suggested) is ridiculous.