|The following is based on Fallout 4 cut content and has not been confirmed by canon sources.|
Maja's message is a cut holotape in the Fallout 4 add-on Nuka-World. It is recorded by Maja. Its file name in the Creation Kit (DLC04Powerplant_MajaHolotape) suggests it was likely planned to be found in the Nuka-World power plant.
Sabir, we seriously need to do something about these know-it-all union guys you hired. They keep complaining that things aren't up to code, that they violate Department of Labor regulations. I thought the whole idea was to hire inexperienced people that don't know the difference. If you end up costing the corporation money on this, it's on your head, not mine.