You say that " as he got sick some things went unpaid" and this included the life insurance policy.
However, many policies include a " terminal illness clause" . This will pay out if the client is diagnosed with a terminal illness, prior to death.
If your husband met the criteria, at the time he was paying for the policy, he may be entitled to a payment.
It would require a medical consultant indicating that, in his belief, the illness was terminal and likely to result in death.
It might be worth getting hold of a copy of the life insurance policy and lodging a retrospective claim.