He wasn't held in a joint prison. Where are you getting this stuff?
He was captured during battle, taken out of Afghanistan, and then charged in the U.S.
The Afghans had no involvement in the whole process.
Irek Hamidullin was held in the Bagram Theater Internment Facility, now known as the Parwan Detention Facility, which has joint control by the U.S. and Afghanistan. He was held in an Afghan prison, first. Where are you getting that the Afghans don't want this and that it's "imperialism"? I can't find references to that anywhere. By every commonly accepted definition of imperialism, this doesn't fit. And considering he was with numerous groups of prisoners brought back to the state's to be tried, and that we have agreements with Afghanistan to do so, I'm not sure why you think this particular case is so special.
It's not imperialism in Britain to send their criminals to be tried in the U.S., it's not imperialism in Afghanistan. Certain high profile cases have people often tried in both countries, especially when directed at multiple countries' citizens. The war in Afghanistan is a U.N. sanctioned mission, with multiple countries from around the world involved. It's not really a case of U.S. imperialism.