The thing he hasn’t realised is that he’s liable to prosecution on top of any clamping fees: https://www.cartaxenforcement.co.uk/%5B/url%5D
What happens if you don’t pay
If you’re registered as the vehicle’s keeper, you’ll get a letter saying your vehicle has been impounded and will be disposed of unless you pay all the fees.
You could also face prosecution with fines of up to £1,000 as well as paying any arrears of vehicle tax owed and costs.
Unclaimed vehicles could be disposed of or sold after 7 days, or 14 days for more valuable vehicles.
I sincerely hope that when DVLA aren’t able to recover their costs for towing his car when selling/scrapping it they prosecute him with the full force of the law.