W class is the highest booking class on all flights operated by non-787 aircraft.
Business Class is only sold on 787 aircraft, for such flights, even domestic, the respective booking classes (J C D) are available.

What I suspect is some kind of table maintenance error:
Likely, Amadeus is maintained in a way that WS operated flights sold by AFKL will book into W/O/R in WS inventory by default (irrespective of the AFKL booking class) since only a handful of WS flights even have Business Class (only the ones operated by 787).
In fact, AFKL is selling J/C/D/I/Z class on their codeshare flight numbers operated by Westjet Encore Dash 8-400, where there is no Business Class anywhere left, right and centre.

I experienced similar issues and booking the WS segments under the WS flight number solved the matter.