My Mom is 93 yrs old and is starting to fail. She smells, her dog craps all over the house, she has maggots in her trash. She lives alone and will not

Call the office of Adult Protective Services in the county in which your mom lives.  Tell them your concerns, and have them start an investigation.  If they find all of the conditions you indicate, they will file for a guardianship.  Or, if you speak to an elder law attorney, you can file for the guardianship.  If your mom is in an unsafe condition, is not taking care of herself, then she needs help, even if she does not want it.