Could you do other events for the harpy and the cat?
Viewing post in Monster Girl Hunt - 0.3.02 public version comments
Requests to advance particular monster events is reserved for higher tier patrons.
If you would like to know what is currently scheduled all patrons get access to the progress posts.
Other then that you just kind of have to wait for them to come out when they do. All monster will get a handful of events at the least, so don't worry too much.