I think I've seen this reported before. I believe SQX team explanation which is that the selection algo includes all the neighbors too so sometimes the red square is deemed best because of it's good neighbors. By design this will happen occasionally. Its a small (presumably insignificant) cold spot inside the center of the best hot spot.
it looks for robust combination where (according to your config) in 5 x 5 cells at least 20 out of 25 cells are green, and the recommended combination is then the middle cell, doesn't matter if it is green or red.
The idea is to look for a robust area, not just one cell.