If your mom’s insurance policies don’t name her children as beneficiaries, then she should change that now. She automatically benefits from Medi-Cal services because she receives the ISS.
Upon her death, the California Department of Health Care Services will assert a claim against anything she owns in her estate that is not spent on funeral and burial expenses.
If the insurance pays out to her estate, she will be subject to Medi-Cal’s claim for reimbursement, and whatever is left after that will end up going to your mother’s creditors.
If you are the beneficiary of your mother’s life insurance policies, then the money will be transferred directly to you upon her death.
Since the insurance money will not be part of its probate estate, it will not be subject to claims from its creditors. You also won’t have to reimburse Medi-Cal.
You are not legally obligated to pay your mother’s debts, but that will not prevent her creditors from asking you to pay them back after your mother dies.
If they do, send them a photocopy of your mother’s death certificate with a note telling them that your mother died with no credit and was on SSI and Medi-Cal. It’ll have to take care of that. If they keep asking you for money, don’t give them anything.