How about not confiscated?
Was in New Orleans for the Jazz Festival.
My wife gets headaches, so we brought an ice bag like this one:
In the morning we fill it with ice in our hotel, and toss it in a backpack. We empty the water at the end of the day.
On the last day, we gather our luggage and gear and head to the airport.
When we got home I realized that my backpack went through the airport scanners with the ice bag full of water. Probably about a quart.
I think that might be above what's allowed.
I don't know you, and I certainly don't know your aunt and uncle, but I would generally assume in Nazi situations that "even after" probably means "particularly after" even if they don't admit it.