I'm not sure if this is an absurd idea, but is there any chance that some of the Irish Palatines who were sent to Ireland in 1709 immigrated to America in later generations? I know some ended up in Canada. I have two surnames in my family tree that appear to be overtly German intermarried in Pennsylvania with original Pennsylvania Dutch Palatine immigrants but originate in Ireland in the late 1700s (1770s). One name, in particular, is Depp. Any chance it could be a skewed version of the Irish Palatine family Daub/Daupe/Doube/Doupe/Dobe/Dope.