I would make it a quick dip, but if there isnt a big chunk of rock with it i really wouldnt worry about it.. i dont think there is really anything that eats leathers. Im not 100% sure but i dont see plain RO water doing any damage in a short dip
RO water will be fine. 5 to 7 minutes, no longer. Do not add any of the dip water to the DT.
An iodine dip would work, too. Follow the directions on the disinfectant.