have you tried a tyre shop to see if they can just do a wheel alignment?
sometimes its just something gone loose.
i understeered into a kerb at 80kph, buclked both wheels on that side and it wobbled liked hell (About 5cm of movement at 10kph) with straight wheels back on.
a wheel alignment fixed my algnment problems
God was on my side as if i had climbed the kerb i wouldve hit a pole it wasnt even a hard kerb either.. one of those 45 degree angle ones that you can drive up slowly