My extension to stay (Non-O) ran out after my cancer operation 3 years ago. I couldn't get out of bed at the time. Chiang Mai Immigration were superb. My wife went to see them with a hospital letter, asked her to come back the next morning and processed it for her in 20 minutes. Given the circumstances and a sympathetic IO they may even waive the fine. I would advise going to see them in person straight away and ask for their help. Good luck to your friend.