Actually This Is Not Uncommon
Same situation as when a husband brings home an appliance thinking he is "helping" Madame, when in reality it is anything but.
She who uses it should get to pick it out, that is what I say!
Back to cleaners refusing to use this or that appliance, product or cleaning method:
Good housekeeping involves a system and methods that get one where they want to be. This is regardless of if one is the homeowner or hired help.
One famous case of a non-starter for laundry appliances would be ironers (often incorrectly called mangles). Many housewives received the things back in the day and found it was more trouble than it was worth, and went back to ironing things by hand. Even today am told many maids/housekeepers presented with a Miele ironer stun their employers by refusing to use the thing.
If the maid in question is from another country,and is not familar with toploading automatic washing machines, then one can understand her wishing to have the Bosch set returned.