I hope one of his own people kills him after he flees the country.
Just looking at how its shook out over history
Nguyễn Văn Thiệu in south Vietnam escaped his country, settled in Boston and lived quietly for 40 years and died of natural causes
Ngô Đình Diệm didn't fare so well and like Malopox said, caught a CIA bullet during their coup
Pepe San Roman who led the bay of pigs invasion was captured and imprisoned, but released by Castro a year later and settled in Miami and lived quietly for 30 years and died of suicide
Lon Nol who we backed in Cambodia, escaped the Khmer Rouge and settled in Fullerton California and lived quietly for 5 years and died of natural causes
Osama Bin Laden, who we backed in Afghanistan OOOooooohhhhhhh right
Anastasio Somoza Debayle fled the Sandinistas and escaped to Miami with a lot of Nicaragua's national treasures, but Carter denied him asylum and he settled in Paraguay and was assassinated a year later
Hamid Karzai and his family still live in Kabul and the Taliban respect him enough, while Ashraf Ghani fled during the fall to Uzbekistan and settled in Dubai and has been there since
I think its far more likely Zelensky settles in the west somewhere. Russia isn't about to storm Kiev and take him by surprise, and while there's a strong potential for a power vacuum after US support dries up that results in a coup by Banderites seizing control, even in that scenario its more likely Zelensky survives to flee to the west and starts driving ubers in Philly.