water damage on leather fireplace screen

I inherited an antique leather fireplace screen, which is painted with a butterfly, a lovely understated peacock (tail down), flowers, etc. The painting is quite delicate and attractive. We don't know the history, since we found the screen in the back of the basement in Ohio after my uncle died about 30 years ago. It had been there many years.

Unfortunately we recently had a plumbing leak that soaked our living room; the black leather of the screen now has a white haze in the area where the water splashed it.

Does anyone have any ideas how to clean this? Also, since we know so little of the history, does anyone have any information about that?