Lincoln Gap Falls

According to the group Friends of the Mad River, this falls is on National Forest land, roughly 3 miles up Lincoln Gap Road from Route 100 in Warren. We haven't yet been able to locate the falls, but the coordinates we have listed look promising. Location is approximate.
To further add to the possible confusion, the Friends of the Mad River suggests that this waterfall IS Hartshorn Falls, not the series of falls further down the river, near the confluence with the Mad River. Still working on clues...