'houdini' villagers disappearing without dying

Villager disappeared in a confined village adjacent to an iron farm - does not appear to be dead, just... gone. Villager is not being replaced, in spite of many hours with villagers being stocked with bread. Private survival server. Searched for missing villager using X-ray within range of village, no results. Suspect "houdini villager" mentioned on reddit. Village population bellow number indicated by valid doors. New problem since 1.10. Village had been running for over a year without incident. Admin stumped. Server restarted daily.