Update: Westjet customer service replied fast - lots of reasoning why they did or did not do this and that and what was being offered in similar cases.
At the end, the affected pax got 100 Westjet dollars. Considering the major inconvenience and forced overnight stay, this is very measly.
This just confirms what I knew - loyalty as we knew does not exist any more. In other words - book solely based on price/convenience, not on loyalty to any particular airline.
I am not going to lose any more time asking them for anything.