While I also don't think we'll get to nukes, even an increase from a 0.00001% chance to a 0.00002% chance, it's way, way too close for comfort for me given I have an idea about nuclear contamination, Russian oppression and the Eastern European psyche.
If you approach this logically though, Putler might try to control the media and whatnot in Russia BUT if your banking system go to shit, people will start asking questions sooner rather than later.
So maybe Putin is trying to get max leverage before these talks and hopefully extract enough, so he doesn't look like the loser and coward that he is. But even if gets something resembling a 'success', the sanctions will stay, so Russia is done for, surely.