I'm late to the party, but it does seem like all of the Wiskirchens today come from the same family. My earliest known Wiskirchen ancestor was Mathias Wiskirchen (b. 1821 near Ahrweiler). He came to Wisconsin with his wife (Anna Maria Schmitz) and their children - I am descended from his son John, who married Rosalia Gustin.

I believe Ahrweiler district is near Koln, no? I just do not know Mathias's parents. His father may have been a Joseph Wiskirchen, but that's not confirmed.