Apparently you believe "human and not immune from error" and "following false and unbiblical teachings" are mutually exclusive. I don't. Luther was human and not immune from error and therefore following false and unbiblical teachings.
Later you wrote that "But what interests me most is that the only possible conclusion one can make is that evangelicals ALONE are always correct...they are somehow immune to error". I stated that Luther was not immune from error.
I hold no human to so lofty a position, whether that is Calvin, Luther or Mary. God uses whom He wishes, how He wishes to His glory whether that is Paul carrying the good news or Mary carrying the Son of Man. He uses you and I to carry his message to the world and He uses that message to open spiritual eyes to see His glory.