Many things wrong with your post.
The very issue that the HK Immigration department is that there are locals waiting to be selected and trained and until there are no longer locals willing to take the job, no visas for non locals. Period.
Regarding a massive, stagnant pool of SOs, also not true. The course that CX has chosen is one of cadet intakes, nothing else, so all have to go through the system, the whole system, from induction, ab intio, Adelaide, CX induction, SO training, ad nauseum. No exceptions.
My colleagues and I are flat out training SOs at every level, but the experience and aptitude just isn't there, so it's taking much much longer than in the past, and our system has yet to adjust for that.