Turns out there are two Withlacoochee River landings inside the Ellaville Tract of the Twin Rivers State Forest.
One I’m calling Ellaville Landing, and it’s the last place to take out before Melvin Shoals.
The other, google maps calls Withlacoochee River Campsite, and it’s only a mile or so upstream from Suwannacoochee Spring.
If you have better names, locations, etc. for either of these, please let everybody know.