I'm not sure what to tell you about this. There are some in my kinfolk who feel that the father of a common ancestor, Garrett Shuster may be a Johannes Schuster who lived in New Jersey and he and his wife had several children and one of them may have been my ancestor Garrett and another may have been a Johannes, who might be your Johannes Casper Schuster.
With all the could be's and might be's, I am not sure, since I've not found nor yet seen conclusive evidence linking Garrett Shuster to Johannes Schuster of New Jersey. I've not been inclined to accept the Schuster name vs. Shuster since I was taught many years ago it was always Shuster, but looking through all the genealogy I have to admit it is possible. But like Thomas the Doubter,I have to be shown.
I have passed your inquiry on to some of my kinfolk who know more about a Johannes Schuster.
Sincerely Richard G. Shuster firstname.lastname@example.org