The problem many within my synod have is not that they are self-righteous or better than others, but that they are very concerned because other religions don't recognize sin and therefore, don't truly know the Gospel. We get called names all the time for teaching law and gospel. But if you don't teach law and use it as a measure, why do you need the gospel?? If you don't think that you sin in the first place, why would you even need Jesus?? We are not bigots, we are not idiots, we are bereans. That means, we keep going back to the Bible for guidance and try very hard to protect the Good News, that even the very worst sinner is redeemed by the sacrificial death and resurrection of Christ, our saviour.
Jesus purchased me at a great price. He did the same for you. Nothing I can do will add or subtract from this. Even if our whole synod is sinning, we are forgiven by our Lord and He will still help us to work this out. We often say in my church that we aren't perfect, just forgiven. You can be too.
I'd like to point out, however, that things could be worse. Last month, I read in the paper that a Catholic priest who was the assistant pastor at a church I attended thirty years ago has been under observation by the diocese since it came out that he was giving "massages" at CYO camp. While I have not been in a Catholic church since 1984, it still hit me like the proverbial ton of bricks. Here was the name of a priest that I had liked, admired, and trusted, and he's on the verge of losing his priesthood over something far more serious than praying! If this is the worst problem that your LCMS faces, then your denomination seems lucky, indeed. I can only try to imagine what it must feel like for people who are still Catholic. So, while I don't have the exact idea of what you're going through, I have a similar enough experience to get a tiny glimmer of it.
You speak of forgiveness in your last paragraph. In Rev. Benke's answer to the charges, he seems sorry for having offended people of your church. I hope that for the sake of the good people of New York City that he spoke to on September 23, that his church will forgive him, as his offenses pale in comparison to the offenses visited upon the citizens he was trying to comfort through his ministry. To drop him from the church is to slap all those people in the face.