As a Catholic let me plead with Evangelicals.
Please DO NOT ignore this problem in your church!
It can come back and destroy you.
Study some of the things Billy Graham did to prevent such things from happening. He was a very wise man.
As an LCMS Lutheran, you are correct.
Take steps now. We drew a rather cut and dried policy for this at my congregation. Was painful (no one wanted talk about the possibility), but it is done.