Some laptops and what not are impossible to deal with. If you have a warranty, now may be a good time to use it. The warranty people may have an emergency password that can open any BIOS. If you can get into it, now would be a good time to look into backing up the BIOS with no password. Flashing the bios did sound like a possibility.
You can always hire a hypnotist to make your son recall the password (Or make him quack like a duck). On the other hand, you could lock your son up with nothing but your computer till he can open it. No phone, no computer, no friends, no Nintendo, no games no TV. When he asks you for money, tell him if he can remember the password you will give him $100.00. Bribery is a good incentive.
My brother-in-law's daughter lost their car once and they found out where it was by calling all of her friends. They had left it in the middle of a farmer's field. Seeing it was a work truck, that didn't belong to him, he was quite motivated to find it.
If you call all of his friends, they might remember the password. They probably used some kind of silly password like a character in a game or something like that. If you do not like my post feel free to point out your opinion or my errors.