If your mom doesn't want someone who is going to actually invest the money then the options are a lot fewer. Any bank or money manager would only work with your mom if they can manage her investments.
Does she have an accountant with whom she can discuss her financial situation? It might be a good idea to have your mom speak with someone who would manage her finances, my guess is she prob would benefit from working with a professional.
2010 Porsche GT3
2012 Ford Raptor
2011.75 AW e90 - Sold