Could I just put in a little proviso here that "escaping" may not be exactly what happened, and could rather be Wilhelmina trying to infuse an element of adventure to events, since the Menagerie is never locked and the animals are entitled to roam anywhere and do howsoever they choose.
Nevertheless, she has requested that I make "Wanted" posters for the occasion, in order to assist with their capture.
So here is a little glimpse...
Wanted: Wild Wilhelmina and the Master
Reward: Jelly Beans
If you're eagle-eyed, you might just spot them this Saturday at Old Spitalfields Market (probably from about 11am until 5pm). Details here.