Is it illegal for employers not to pay over pension fund contributions?

No, this is not allowed, in fact it is a very serious offense not to pay over pension fund contributions, for which the directors of your husband's company will be criminally prosecuted. Our law requires that pension fund contributions MUST be paid over the fund within seven days of month end. Of course, it is fraud to withhold this money in the company's bank account as it - and the investment income thereon - belongs to the employee. You should report this matter to the FSB (Financial Service Board) as a matter of urgency.