unfortunately the FilterByBoundingBox method is not working for me in V23. But I agree with you, the x, y, z order is correct for your example above.
public static Box Create( double minX, double minY, double minZ, double maxX, double maxY, double maxZ )
Please find a MWE below.
Probelm: In my case this does not limit the total set to the subset of faces.