Badger_Boom
Regular
My impression is that they are requesting on the basis he likely has information that can help them identify perpetrators worthy of further investigation. Not that they are trying to prosecute him nor arrest him. They were interviewing one of the US Committee a few days ago and the US committee member was saying Andrew could do it over video link (they didn't add "from whatever palace or castle he happens to be staying in at the time").
Everything I've seen has been requesting help on the basis it's the right thing to do not a question of jurisdiction.
That said the man's a fool so I don't read every detail relating to his exploits.
Thousands of documents full of names and dates, and even photographs but they still need a foreigner to help them out? I smell a rat.