I have been edge matching country boundary files using Python which was created by someone from the organization (I'm not a Python Programmer myself). It is the same Python script used for all other countries and it always works fine. Also, the parent boundaries I'm using come from the world map we use for all countries. For some reason, the script did not catch some tiny mismatches for US and Canada shapefiles. I wonder what could be preventing the script from detecting these misalignment. The red circle is where the zoomed section come from.
Also, the files are in geographic coordinate system (GCS_WGS_1984).