I think /u/Cozijo would love to answer this and would provide a great answer, but he's currently in the field. If no one else answers, I would try again in like June.

Well, there's archeological evidence that the first Toltec influences on Chichen happened around 800 BCE.

Locally, there is a lot of legends and oral tradition about foreingers settling in Chichen, but the sources are a mess and it's not really clear if the influence came in a form of conquest, alliance, trading or something else.