Not sure if this will help but this sounds exactly what was happening recently with my sons Jeep. We put larger tires and wheels on it, 32" so nothing too big, Goodyear Silent Armour. Immediately had a vibration between 40-45. Rebalanced, rotated, aligned, had the entire front end and steering checked and finally Road Force balanced them, all with no change. Finally got Goodyear to work with me and swapped the tires to Goodyear Duratracs. Vibration went away. Only thing we can figure was the that setup with that tire just didn't work with the vehicle.

Do you have the stock tires on? Either way if you can I would swap to a different brand or size tire even if you are running the stock ones. Just to know.

Good luck, I know how frustrating it is.