I'm shocked that they didn't have any weekly cleaning service coming by to clean their sprawling estate. Mrs Hackman appears to have been was very hands on.
At a minimum, they should have both been wearing these Life Alert necklaces. They're supposed to sense when the person wearing it falls and will immediately call (through the necklace?) to see if they're okay.

But with their money, there's no excuse for Gene to have not been moved into a nice care home. Or for a live-in nurse to come stay with them.