How come you only consider reporting the business now while you husband had been employed for 18months? Could it be he was happy to turn a blind eye while he was employed?
As the restaurant manager, does your husband not have some reponsability in knowingly working with undeclared staff?
Food for thought.
Well actually my husband did inform the three employees that actually can string two word of english together that their P45s were still in the safe and most likely would stay there for ever. The remaining employees are family members of employer. I'm not sure that he would have risked losing his job crappy as it was(which are very hard to come by these days) in order to get other peoples tax affairs right.