Is a life insurance beneficiary responsible for the debts of the benefactor in M.?

A friend of mine's son ped away suddenly at the age of 49. He was divorced, and his son (aged 25) was the beneficiary of his life insurance policy. Will his son be responsible for his father's debt? There was a loan made to him from his ex father and mother-in-law when he and his wife were still married, but in the divorce decree he signed he agreed to be solely responsible for that debt. I take that to mean that he alone was responsible, but can the insurance policy be attached for payment? Thanks for the help; serious and informed answers only, please.