and you are already getting a poa that will allow you to pay without being on the cc accounts. I have handled the accounts for various family members and that is what we did.
You might want to be appointed representative payee on their social security as well. That way you can protect them from accdentally signing it away. Like at the nursing home. If Mom has already simply take her to ss office tell them what is going on and they will help you fix it.
I paid all bills online or had the bank send payments. I was also designated as the one to call if there was the problem.