I live in Southwest Louisiana, where fire ants are a constant battle. The molasses repellant works for me - I smear it full strength on shovel handle, dig up the mound, and dispose of mound in various ways.
Also heard that spraying dilute molasses / water mix on fruit trees and bushes will discourage fire ants so tried it. The fire ants left all areas within the drip line, but it takes a couple of weeks while trees systemically absorb the molasses. If you have other species of ants roaming around, they could be attracted to the molasses, so be sure you know it’s really fire ants that you’re dealing with. Once bitten by a fire ant, you’ll never confuse it with another species again!
Another organic fire/ant remedy is to use orange oil (I use Medina brand). Two ounces per gal of water, pour about half around mound perimeter and then dump the rest right on top. Average mound is dead within twenty minutes but huge mounds will need more than one gallon. This does normally kill the queen though occasionally she survives and moves or regenerates mound. Safe and relatively inexpensive way to control fire ants.