I have an Emma Keidel in my tree.. born 1877 in Brooklyn. Her parents were born in Germany (not sure where in Germany) who married an Albert KONZE. They married in Kings County, NY in Nov. of 1899. It may not be the ancestor you are looking for, but there could be a connection. There weren't many Keidels in NY at the time. Emma's parents were Louisa and Frederick, both born in the 1840's. Including Emma, their children were:
Josephine (b.1869), Anna (b.1872), John (b.1894), Emma (b.1877), Frederick Jr (b. 1881), and George (b. 1886).