I'm so sorry for what you're going through. There was recently a post on reddit about what to do in the event of a loved one's passing and transferring their points. It seems some programs will immediately shut down the account when the death is reported by you (with potential loss of points), so it might be in your best interest to see if you can get into her excel sheet or accounts and see what accounts have what point balances. From there, it might make sense to concentrate on the highest point balances. We are willing to help you decipher what a point balance might mean as well, because 70k Chase UR points are worth a significant more than say 70k IHG or Hilton points.
Many programs allow you to transfer to household members, authorized users and pool with family members. Other programs do not, or charge a fee to transfer points.
I'm going to link to the reddit post
here but please know that not everyone is kind over on reddit and to just try to bypass any jerk comments.
P.S. I'm not sure how your mom handled paying cc balances, etc and if those were set to autopay, but that might be the first thing to look at.