Read something a while back about how most ferns are actually tougher than we give them credit for, it's just their transpiration rate is through the roof. They lose water faster than a lot of plants, so dry air kills them, not necessarily low light. That lobby probably has consistent humidity from people coming and going, maybe even a central HVAC system keeping things stable. Maidenhairs are the real test though, their fronds crisp up if you look at them wrong. Good luck, mine's hanging in there next to a humidifier.