It might be true that turns 6-8 were shaved off a bit since
this map was first published in the early 70's, but that doesn't make the rest of the map incorrect. And yes it would take some painstaking graphical/scaling work to create an appropriate elevation/distance table. Having been and walked Mosport many times over 40 years, and driven it as well, some of the game tracks really don't always capture the look and feel (particularly in car) of the elevation changes reflected in the elevation profile of the map. Many track-side photos tend to flatten the appearance due to the elevated photo shoot positions. Walking up to corner 5 is way steeper than you think!
It is also true that the elevation map does not capture the often dramatic and sometimes subtle camber of some corners.
Some really good work has been done with simulating the track to date. Diving into the opportunities of all the references may yield some improvement.
Keep up the great work.
Cheers