You don't want them learning to sleep in a nesting box, they will have poo all over their eggs. UGH!! Generally you keep nesting boxed closed off until your pullets are approaching point of lay. Then you can put a golf ball or two in each box to show them eggs go there.
Raccoons are one of the very worst predators, even if they don't kill all the birds, they will leave others so horribly damaged, they generally die later.
They can climb, dig, jump down from branches or rooftops, and have opposable thumbs. They can open any latch you can. I hope your husband is a believer NOW. Painful lesson learned (I hope). Raccoons are notorious for reaching through openings and biting off any parts they can reach.
That's why poultry wire is useless against them. So flimsy, coons can tear or bite it apart. The gold standard of wire is 1/2" hardware cloth securely affixed to framework - not with little zip ties.