I'm not sure as to mechanics of attesting by notary ..one copywrited article by GA attorney specifically says under new rules the notary must be in presence of the maker and the witnesses ....and then there are issues of different GA law as to how a notary is to act ...the POA might be "void" but that's a point to address in GA with counsel of OPs choice .
I might also ask about if one uses a docuement one created improperly, to move or direct funds if that's a form of theft by deception ....as in Insurances
IF SM was listed as authorized user on Dads bank accounts her access of same may well be OK.
And that language for life estate in a will not yet filed for probate bears some careful legal eyes on OPs side as to how that might play out .