Bevendre

This has been answered on Papi’s blog, but I’ll answer it here anyway.  Papillon accepts others into the hive only if they are willing to become changelings.  Help from a regular pony, or one being accepted into the hive would be construed as a betrayal of their race should any future negotiations between Papi and the Princesses not go well.

Papillon believes that if a regular pony joins the hive, and they are found before she is ready or if peace cannot be achieved, then the pony will be labeled a traitor, and severely punished for it.  As such she only accepts those willing to become changelings as changelings are not subject to the laws of Equestrians, and can be protected by Papillon and the hive.