Jefferson and Hamilton (and other British subjects who'd been to India) did the first Ohio Valley surveys after the Brits had taken it from the French and noted that the territory was EXCEEDINGLY FLAT, just like the Indian plains.
Hence, the name Indian~a was applied.
Has nothing to do with the Indians ~ just the lay of the land and the education of the surveyors.
Jefferson never traveled west of the Appalachian Mountains, or to India. I don't know about Hamilton but I don't think he ever traveled west of the Appalachians either.
This is the first time I ever heard of Indiana being named for India--I had always connected it with American Indians.