Paul,
The changes look correct except that you linked
America/Rainy_River to
America/Toronto instead of
America/Winnipeg.
Rainy River is west of 90°W and needs to remain on Central Time.
David,
I don't deny that there may have been some small reserves that did not observe daylight saving.
They could still be added to the database if somebody wants to do the research and provide appropriate names.
However, it would be wrong to use the names of existing towns and cities to represent small reserves that exist outside of those towns and cities.
-chris