I had a infinti fx35 with the same problem I know I know different car + wider stance and wider tires, but just an idea. I did a lot of things so I can get rid of it. Its a big issue on that platform as I found out later on forums. Removed my spacers helped a little bit but still there... tires balanced few times, vibration still there... Finally some noise started at certain angle of turning steering wheel so I pointed that out and after steering rack replacement and tightening (there is some bolt for that) vibration disappeared. I hope in this case its not that, cause I dont know if there is a way of to find it unless it start making noise. Hopefully we dont have problem on this platform.
I would recommend:
check control arms bushings again and steering ends (lift the front up with steady lift and try pushing the wheel back and forward, left and right) mine were bad so I replaced them with M3s. I had 60 000 miles on them at that time.
roadforce balance tires again at a reputable shop (not pepboys or sears) on a hunter machine.
get rid of RFT tires (i dont know if someone else had same experience like mine but with mine I did rebalance them a few times and every time they were off... if I remember correctly.
I dont know if it could be a bad bearing?