No, you're not overreacting. My parents tried to indoctrinate my son and when he was about 8 years old he came home from an overnight visit, visibly distressed and crying.
He was already seeing a doctor for anxiety (generalized anxiety disorder) and when she heard about this, she forcefully told us not to allow it anymore at all. It was obviously very bad for him.
I had to have a talk with her and didn't allow him to stay overnight again for a long, long time.
I found out she was sneaking behind my back, bought him a suit and took him to the meetings with her! That got stomped on, too, with a request she look into the pedophilia scandal.
The point is, the JWs, even our parents, have no respect for parental authority. They will sneak and lie and think they are doing good.
Please put your foot down now.