To be fair: Phone cameras will pick up infra-red beams, such as those used by remote controls and security cameras. This is actually a good way to see if your remote is working. That pink-purple beam might be the result of some sort of infra-red light. Now, as for why its doing that? Not a clue. I don’t for an instant think the Mayans had infra-red spotlights.
Yeah, it really does look like some sort of a digital artefact resulting from the camera processing the image weirdly. When I was reading the description, I was thinking that it might have been the precursor to a lightning bolt, which rises up from the ground towards the sky. But that’s not what is in the image.