In the absence of actual documentation one is thrown back on conjecture. It is hard to conceive that the ballads did not come across in all waves even starting with the Pilgrim Fathers. Off hand I can't remember actual ballads but I'm sure I remember there being some of the Child ballads found in America that have died out long ago in oral tradition this side of the pond.

You might find it useful to look at 'A Pioneer Songster' edited by Harold W. Thompson. The book is an anthology of ballads from the Stevens-Douglass Ms of Western New York, 1841-56

It has versions of Child, 45, 84, 112, 268, 283, 285, 287, 289, not the most typical of Child Ballads, but Child Ballads nevertheless.

There will be other manuscript collections. I suggest you repeat your request to the scholars on the Indiana Ballad List.