and he needs to show all relevant documents to nearest police station eg. insurance, mot etc..
Nothing at all to do with the visa issue, but I fear this might get worse. He has yet to produce his documents at the Police Station. They might conclude that he was driving without insurance, given the insurance was probably invalidated by driving on a provisional licence without an accompanying driver.
He has been living here for nearly 10 years. Surely he was aware that he was not allowed to drive unaccompanied on a provisional licence?
The visa issue? Based on Police action to date, hopefully there will be no effect. But a subsequent prosecution for lack of insurance, or worse, lack of production of documents at the Police Station and lack of insurance, might have an effect upon an application for Naturalisation in due course.