I understand but the thing is that the cost of the connecting balcony stateroom is the same as a non-connected balcony stateroom. NCL isn't going to guarantee Haven access for that stateroom without a price increase. IF NCL gave a price for that stateroom with access and a price without Haven access, it would be more clear. I've suggested that before but NCL doesn't care what I or anyone else thinks is a good idea.
That could work against your plan. In the past, getting minors in a connecting room made it easier for those minors to have Haven access. 2 adults in suite, 2 minors in connecting wasn't a problem. Unfortunately, what would happen is that a family of 4 (2 adults, 2 kids) and their family friends (2 adults, 2 kids) would book the 4 adults in the Haven and the 4 kids in the connecting. All 8 would get Haven access for much less than booking 2 suites. NCL has done different things to prevent/lessen that from happening. Things aren't consistent with NCL and different concierges will give different results.
The phone reps are (mostly) useless. They could tell you "yes" and the concierge on the ship can tell you "no". They could tell you "no" and the concierge on the ship can tell you "yes".
If NCL did institute a different price for connecting with access, I'd support that. Give people the option. However, if total strangers are in the connecting, they might knock on your door and ask for you to "hook them up" and even offer you $$ to ask the concierge. It's just messy.