The critical question centers around the cost of your mother's Assisted Living Facility and her medical care. Perhaps your sisters, who you acknowledge are good with money, have no choice but to sell the house in order to continue paying for your mother's required care. Even if your mother revokes the present POA and executes a new POA naming a different attorney-in-fact to act on her behalf, the new attorney-in-fact will face the same dilemma: How will mother pay for her care?
Because it has been over a year since your mother left her home and moved into a medical facility, and because it is medically impossible for her to return to her home, your mother may not qualify for public assistance when she owns a significant asset that could be liquidated in order for your mother to pay for her own care.
You should read this government publication:
U.S. Department of Health and Human Services
Medicaid Treatment of the Home: Determining Eligibility and Repayment for Long-Term Care
In particular, you should note the following:
An exempt "home" generally becomes a countable asset -- that is, its equity value is counted against Medicaid eligibility limits -- if the owner has no living spouse or dependents and
--Moves into a nursing home or other medical institution on a permanent basis without the intent to return
--Transfers the home for less than fair market value, or