@astxov82 ,
A good EP is like gold to help you and your mother with this. I have an excellent one a Mayo Jacksonville.

Has anyone suggested magnesium? It was recommended by my EP. It did seem to help. Lot of discussion on what type but let your EP suggest that.

Stress and anxiety can cause AFIB. Reducing that can help also (no my opinion comes from my EP). How is her weight? My EP also says excessive weight can add to AFIB. I agree with other posters about caffiene. But every reacts to caffine differently and may or may not be the culprit. Too much of it can't be good. I limit mine to an absolute minimum.
Good luck!