Racism in Cast Listings?

I was looking at the page for Woman Walks Ahead with Jessica Chastain and Michael Greyeyes in the two main roles, which is obvious in the poster for the film. However, immediately below in the "Stars" summary list, Michael Greyeyes is omitted; it lists Chastain and two other "white" people with MINOR roles. Sam Rockwell, who has a significant role, is also omitted. Then in the "Top Cast" section, Chastain is listed first, Rockwell is seventh, and Greyeyes is TWELFTH! The listings are not alphabetical, so what is IMDb's algorithm for this? Because it may not be intentionally racist, but it is certainly problematic.