My current employer was called, asked about my job, and yes about my NOC duties as well. They also sent him a copy of my submitted COE and reference letter which was given by my employer for them to verify if it wasn't edited in any way, and if it were the letters they have given me. CIC made my employer sign a letter of confirmation and sent back to them.
As for my previous employers, they were called as well, just verified what my position was in the company and also sent them a copy of my COE from them to verify if those were true & correct. They contacted every previous employer in different countries I worked, all were asked for document verification ( 2 of my supervisors were contacted).
Being processed by Hong Kong VO is not impossible because CIO assigns applications to different VO's for workload purposes. Mine was processed in Manila VO even if I am an Inlander.