Earlier quoted context omitted.
Probably no compensation. Under "English" law (Canada is a Commonwealth country), the wrongful conviction will probably to taken to be without malice and reasonable given the information the US provided, so tough luck. He might be able to negotiate an ex gratia payment, but this will be entirely at the whim of a politician, who will be looking to avoid being criticised for giving away government money
We used to charge innocent men for room and board in prison after being released here in the UK not long ago. They only changed this in 2023 after uproar in a recent case of an innocent man being freed.
Although asterisk: those costs were being deducted from the final compensation. Still disgraceful that even happened.