Basically, I don't agree that this pension fund is solvent. The minimum funding requirements exist for a reason, because underfunded pension funds are probably going to blow up at some point.
What happened is, he promised a certain pension to his employees. Then, he put his money in a pension scheme that actually wasn't charging enough. Now, years later, once some sane accounting rules are put in place, it turns out that there isn't enough money to live up to the promises that were made. It sucks that a decision like this would make a business go bankrupt, but that's what happens when you make financial commitments that you can't afford to pay.