When I had whitespot (well, my tank did!) I couldn't catch my amano (aka yamato) shrimps so they had to take their chances. I use King British Original Formula WS3 at half dose because I have loaches. The shrimps went into hiding for the duration of the treatment but they survived.
If you've already removed them you don't need to treat the shrimps. The parasite won't attack them, only fish. But there could have been some of stage 2 (the cyst on the bottom of the tank stage) that got transfered with the shrimps. All you need to do is wait until all of those possible stage 2 parasites have moved into the free swimming stage 3 and died without a fish to attach to then it'll be safe to put the shrimps back. It's going to take several days to treat the main tank, then a few more to remove the medication with carbon, so by the end of all that it should be safe to put the shrimps back in.
This is what I did with my snails, which were a lot easier to catch than the shrimps.