If your husband and his brother are the primary beneficiaries on the second policy, they should be filing a claim with the insurance company.
If the ex-wife cannot claim the benefit due to the divorce and there were no contingent beneficiaries, then the benefit will almost certainly be paid to the father's probate estate. If father has a will, the probate estate will be distributed according to the provisions of the will. If not, it will be distributed according to the provisions of MI's intestate succession statutes.
I haven't seen the paperwork yet but supposedly there is a very crooked uncle that is filing as heir of the estate.
What does "filing as an heir" mean? Filing with whom? Do you mean that the uncle is filing to open probate and be appointed as the personal representative of the estate? If that is the case and there is no will nominating a personal representative, your husband and/or his brother could file to open probate and be appointed. They would likely be given preference by the court for the appointment.
Unless the father had a will naming the uncle as beneficiary, the uncle does not stand to inherit. With no will, and presumably no surviving spouse, the father's children would stand to inherit under MI's intestate succession statutes.
"Look, sir, we can't just do nothing."
"Why not? It's usually best."