Yes, I am very surprised actually. I know in my ministry I would never allow something like that to happen. However, people aren’t always as revealing about themselves as you would like them to be. In other words, during the screening process, whoever is responsible for organizing baptism classes at your church may not have been told by this family that they are going to disseminate heretical beliefs. Then again, the staff at your church might be heretics too.
Definitely bring it up with the pastor. That might help clue you in on what kind of parish staff you have.
I think it’s a huge deal.