If Mom has not signed a release Mom has released nothing. The signed document may have some evidentiary value…but it certainly does not curtail mom’s rights. If mom dies there may be other complications. Some one need to contact a lawyer on mom’s behalf.
Based upon the facts as you have laid them out, it does not appear that the release would be enforceable. Given her age and condition I would suggest see seek a local personal injury attorney as soon as possible who should consult with her for free (in office, home, or hospital), review the release and facts, and can advise her how to proceed.
I have not heard from the facts, reasons why you think casino is responsible for the fall. Slip and fall cases are difficult not to mentioned the supposed release form which would have to be challenged. Nevertheless, you should contact a local personal injury attorney to see if they take the case.
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