I stealing other peoples ideas now.

So, here's some good ideas that I've found by searching YT.
Guess the Yorkie: You bring out like 5-10 Yorkies and everyone has to guess what Yorkie belongs to who. If you have ex-pens you could have the Yorkies in there instead of having someone try to hold all the Yorkies and their leashes.
Also, another type of guess the yorkie would be where you blindfold the owner and they have to figure out which yorkie is theirs by touch and smell.