We were in a verandah rooma nd yes, the verandah dividers can open on both sides all the way down the ship for the most aprt. Deck 5 verandahs have breaks along the length of the ship but the rest seem to connect the whole way.
As for the tool, it looked like a hex tool of some kind that maintenance or room attendants must have. There's a lever you just slide over and then the wall folds in on itself and you get a space that is half as wide as your verandah to walk back and forth in. It's not big enough to fit chairs in the opening and relax, unless you wanted to be a part of both sides (head in one, feet in another).
We didn't take pics, so I'm sorry I'm not able to upload any here.