I'm not sure about that. Hotel will sell you some food (they say they don't serve, but sell heatable food, so I'm presuming there's a microwave available if needed), but you can only reach it until 22:30. If your Schengen arrival is delayed, your family member(s) might be stuck Schengen side.

Is it feasible that those arriving NS at 6:30 will stay in airside hotel, but those arriving S at 9:50 will stay landside, and meet in the morning?