You can get detailed plans on the internet. It’s getting certain components that are difficult. However they managed to build plutonium bombs in 1945 with more primitive machine tools than are available by truck shipment today. No way did they need this guy to build nukes.
“No way did they need this guy to build nukes.”
I agree. Ukraine has its own share of accomplished physicists. I assume he was there because of his laser-guidance expertise.