Seems like a very unlikely rumour, but if so:
Exactly what authority and capability does the company have to deny travel rights/detain someone?
And exactly how do they think they can ignore HKG laws by refusing to supply the IRD with whatever documentation they must provide?
Is this the same company that is in deep doodoo way over their heads after all these years of pretending that individual taxation issues are the individual's responsibility and they don't have to do anything ever?