Hi Melanie…
the least painful way I can think of to do this would be with the three-way color corrector.
it’s secondary section includes eye droppers and controls to create a mask to let you correct within areas that match a specific color (range).
So you will likley need 1 CC per shade of white to control and balance them out to be the same.
But once you get one clip…you should be able to copy and paste attributes to other clips…
you could then do overall color correction (non secondary) on top of that…
hth,
Alex Udell
Editing, Motion Graphics, and Visual FX