With all the financial problems at ESPN, they devote very little resources to recruiting and Kanak is a late riser in a forgotten about state. As a general rule, ESPN typically has the least reliable rankings I’ve seen.
The real answer is that ESPN has a very very small recruiting staff and does a terrible job scouting the midwest. They do a terrible job scouting period though. You should never look at ESPN's rankings. 247's in house rankings are by far the best.