lodging

Have you searched websites like VRBO, airbnb, Flipkey? Even Priceline; http://travela.priceline.com/hotel/POI-Weener_Germany_Weener_Niedersachsen_Germany-94499106.html

Is the problem that you cannot find A room that will accommodate 5 people? That can often be difficult in Europe and maybe you should be looking for an apartment.

I used the town website and found one vacation apartment (Ferienwohnung) for 5 people, but it had a double room, a single room, and two rollaway beds (probably set up in the living room). The website is in German (but, you are going to be in Germany). Realistically, if you are only going to be there for one night, a Ferienwohnung is probably not going to work. Although the per night price is probably less, Ferienwohnhngen often have a minimum stay requirement of as much as a week, plus a "Endreinigung", (final cleaning charge) that make one impractical for only one day. You might be better off splitting up and taking a double and a triple room.