It is only supposed to show buildings that allow firing from 2 or more windows at all angles of attack on the tac map. the church has doors on each side no windows for example basically buildings that would provide 360 degree fire ability. but it also shows buildings that are blown up that would have 2 or more windows, so not sure.
Actually the church does have 360. There are windows above the doors.
It's funny that no one has spotted this before. Or if they have my mistake but I noticed that during the process of writing my new Ostheer guide I noticed that there a number of missing structures from tactical maps. Here are a few examples: