I did explain and play through one position of the "E Hexatonic" scale in the Dickey Betts Artist Study. Although the "Scale Finder" in the Guitar Tricks Toolbox doesn't have "E Hexatonic" as I used in the Dickey Betts Artist Study, if you choose the "Mixolydian" scale in the key of 'E' from the GT Toolbox and leave out the '7th' degree (as I mentioned in the Dickey Betts lesson) you'll be playing "E Hexatonic."
Hope this helps!
-Dave