Locate Missing Insurance Policy

I am the extractor of my father's estate who's wife passed a year and a half before him. My step mother's family went through all the paper files after her death while my father was alive. When my father passed, I noticed there were many documents missing. One of them was my step mothers life insurance policy. I was able to get bank records, but it did not show life insurance payments. There were transactions made to an account that only lists as "Internet Transactions" and "Mobile Transactions" to which her family was managing. Based on my past conversations with my step mother, I know there was a life insurance policy. I believed she worked with her family to cover their tracks of this policy and they cached it out while my father was still alive. In California, even if her family was listed as the beneficiary, my father was entitled to half the payout. Her family is uncooperative on the subject. Without a policy number or even the vendor, how would I go about contacting life insurance companies to find if there was a policy? I am the executor of the estate, have the probate letters, father official death certificate, marriage certificate, and a copy of my step mothers death certificate (not official).

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Spouse Beneficiary Rules for California Life Insurance Policies While the spouse does not automatically become the beneficiary on a life insurance policy, he/she may claim half of the benefit after the insured spouse’s death if the policy was purchased during marriage and the premiums were paid with community funds. Suppose the insured spouse designated someone other than the spouse as a beneficiary on such a policy. In that case, the spouse’s community property right to half the benefit will override the beneficiary designation.