Twenty-five is a good turn-out, and you can do almost anything with it. Agree about five random-age people though. (I once had one eager couple get out on the dance floor, turning towards me and expecting to be led into happiness. Yikes!) Better to have a small eager crowd than a huge one that doesn't/won't/can't dance and sits there watching.

For circumstances like this I have recordings for stuff like Chicken - Hokey - YMCA. Add some Civil War "germans" like this one.
https://youtu.be/HMBfFo9Rykw

And try boosting their turn-out. You might invite some of the local dance-aholics (not the sweatband snob types). If they have a FB event page, share it. If they don't, make one.

Let us know what happens!

--Karen D.
voyeuring in Grand Rapids