I don't understand what you mean by "denominational mentality". According LCMS rules, scripture is the sole standard by which all of its teachers are judged (Formula of Concord). The charges brought against Rev. Benke were based on scripture alone (e.g., Ex. 20:3; 1 Cor. 10:20, 21; 2 Cor. 6:14-18; etc.) not arbitrary synod by-laws.

The LCMS does not consider itself to be a real church. It is a voluntary synod of ministers and congregations who are in confessional agreement. It has no power to excommunicate or even defrock. The LCMS does have the power to suspend false teachers. When the LCMS overturned the Schulz suspension of a false teacher, the synod was acting contrary to Paul's instructions(2 Thes. 3:14, 15).