Not specifically. I wasn’t even considering an island, but it may be related.
Basically… Vent Stacks and Waste Stacks…
You said this structure is 100+ years old. Visualize what the building looked like before. What kind of plumbing system did an old theatre have back then? Not much! Now how do you think the system would have been modified to handle all the lofts that were developed. You know they re-used as much of the old original stack as possible, but in no way would it come close to handling the new demand. The original stack may have been converted to “vent only” (no leaking) and all waste was installed new (without a stack penetrating the roof). I guess it would be very similar to an island vent system, just in the walls and not an island.
Sorry if that doesn’t make sense. I’m heading out now, but will check in later and try to post a graphic, if I can locate one, to help explain it better.