Nasty buggers...one of our dogs ran through a fire ant dirt mound and I got the hell bit out of me taking care of him. Had to dunk him in a tub of soapy water to suffocate the bastards.
Have you tried instant grits?
Worked quite well on the fire ants in SC.
Happened to our poodle on the way to Houston. Stopped to let him go potty, didn’t notice anything when he got back in the car until the kids started screaming! Oy, they were everywhere in about 5 seconds. Awful.