In response to why Johann Karl doesn't appear anywhere and there is no record of his marriage or children is not because he married a non-noble. It is because he married a non-catholic. He was injuried in the 30 year war and nursed back to health by a milk maiden. She was a protestant, so when he married her, he gave up his title. I believe the official noble family records listed him of dying from a wound during the 30 year war.