Fiore Di Latte IS Mozzarella in water and his just stood outside long enough to dry a bit...?
Ding, ding, ding...we have a winner!
Just what you said, fior di latte is FRESH cow's milk mozzarella. In Naples when you say mozzarella, it's assumed that it's from buffalo milk. And I think your observation is correct. He dried it out.
I love the fresh mozzarella (and burrata) at Casa della Mozzarella off Arthur Avenue in The Bronx. Orazio Carciotto makes incredible handmade mozz. But it's way too wet for pizza - at least how I use it. I asked him if he could make fresh mozz but "step down on the water" which is possible (Mike's Deli around the corner from him offers a "pizza fresh mozz" cheese that does just that).
Orazio only makes mozz one way so he suggested that I slice the mozz, but it on baking trays and leave it in the walk-in, uncovered, for 24-48 hours. I did just that and one time I got the most incredible mozz for pizza. It kept it's beautiful white sheen, the cheese pulled, the taste was great. But the other times I did that, some were watery, some too dry, etc.
All to say, it can be done - and as much as I love Orazio and his shop, I can't make his product work for me.
On a smaller scale - have at it! See what you come up with. Good luck!