The textbook that the Fantastic Beasts movie was based off of recently got an update, adding six new creatures and a new foreword. The symbols of three of the Ilvermorny Houses - Thunderbird, Horned Serpent, and Wampus, are all included in the new version. So why isn't the last one, Pukwudgie, also included? All of the creatures included in the update are originally from America, but Pukwudgies are also native to America, so would be eligible to be included.
Their description quoted from Pottermore (for now, the only source for information on Pukwudgies):
The Pukwudgie is also native to America: a short, grey-faced, large-eared creature distantly related to the European goblin. Fiercely independent, tricky and not over-fond of humankind (whether magical or mundane), it possesses its own powerful magic. Pukwudgies hunt with deadly, poisonous arrows and enjoy playing tricks on humans.
So, why wasn't the Pukwudgie included in the updated version of "Fantastic Beasts and Where to Find Them"?