So my question is pretty much, was the loss just bad luck or have I missed/misunderstood something?
I would say that it was not bad luck since he beat you in the first 3 quarters. The 4th quarter was garbage time.
Be careful of game ratings and points per 100 shot ratings whenever there is garbage time. Your pts per 100 are inflated slightly because of it and his pts per 100 is also lower. It gives you a clear picture of the whole game. However, to know why you lost, you would need an analysis of quarters 1-3 only.
Run of the Mill Canadian Manager