[2019] No ARKaeology Event this year, will we have Halloween Event?

Wildcard works on ARK, Grapeshot (which is like a sibling team) works on ATLAS.
Dark & Light, Pixark, ARK Park, Wushu Chronicles, and Fear the Night are all either developed by Snail Games or developed by other studios/teams and published by Snail.
Outlaws of the Old West is, to my knowledge, not in any way related... it's not even published by Snail.
I just wanted to clarify those points, but otherwise you are correct, our team isn't massive.
Current events and plans can have impact on holiday event planning.
That said, a Halloween event this year is not out of the question.