Aw sorry dude it was like 20 years ago at this point. I do remember it started with an I and it was in the middle of North Carolina near Advance. They may have closed it since then.
Could it have been the Northbrook International Ultraport Ultralight Airport? It gets pretty close to your description: one grass runway, listed as privately owned by a James K. Peeler and nestled in underneath the Charlotte-Douglas International Airport's airspace in North Carolina.
The story reminds me of Llandegley International airport[1], except in your colleague's case there actually was somewhere to land!
[1]: https://www.independent.co.uk/travel/news-and-advice/wales-a...