Family Sharing and Disney Plus

I have a Disney Plus monthly subscription through iTunes. I also have a family sharing turned on for me and my wife. When we purchased this subscription I was completely led to believe it would work for the members of my family.

It is not working for her. And after talking to Disney Plus staff about it I was told "we are not Apple." Such attitude absolutely confirms they are not Apple. Nonetheless why is this not working and what do I have to do? I wish I could have Disney resolve this for me but they are clearly terrible.

Likewise, it is too bad this is not an available subscription through Apple TV as that would solve all of this.

Thanks in advance for any help here.