This is my understanding. The insurance payout isn’t a part of the deceased’s estate, it’s a contract between the deceased and the insurance company, and if there’s anything the insurance company lawyers can do, it’s write contracts.Did the person buying the insurance policy specify that beneficiary or was the insurance paid to someone else? If the named beneficiary got the money you're SOL. You can challenge anything if you can afford the lawyers fees, but winning is harder if the person paid is the named beneficiary.