"i can hear you both too bad".... what a telling statement. When you lost the ability to focus you can not tune in one sound and ignore others. All sounds come in without alteration by our brain... and can be completely and totally overwhelming to somebody that has trouble trying to decipher what one person is saying in a quiet room. I have seen it over and over at the care facility. One in particular, I can carry on a conversation with her in the quiet of her room but she refuses to respond at all in the noisy commons area. I see her eyes darting from sound to sound rather than being focused on where one sound is coming from. It's like trying to pick out that 2nd french horn in a full orchestra with headphones and an untrained ear
I do understand the balance between firmness and kindness coupled with knowing how to respond to dementia patients. That takes experience and training. A few have an innate ability but they are very rare. Sometimes it take conversation with the care giver to let her know exactly what you want. Each patient responds to different methods. My Mom will buck up and resist if the caregiver is domineering with her... but you can sweet talk her into just about anything. Maybe this gal, since she is ok with Mom, might be worth working with for a while.