I've made an alcoholic root beer, but I used Splenda and lactose for the final sweetening. Ferment it all the way out, sweeten with a non-fermentable, prime with a fermentable and bottle.
Remember one unassailable statistic, as explained by the late, great George Carlin: "Just think of how stupid the average person is, and then realize half of them are even stupider!"
"I would like to die on Mars, just not on impact." Elon Musk