I want to add that saying someone is "independent" is a bit irrelevant in Canada, even from a simple employment aspect. The law decides the status, not the agency. For instance if someone wants to pay their workers as independent contractors and the workers are in total agreement, the courts have still overturned that status in some cases, because the workers were not acting independently according to the legal criteria of the word.
I suspect the same would be true of the elders and I believe there was one case in California recently where the courts found the WTBTS liable even after they had tried to claim independence.
One of the criteria for independence in Canada, is that the work is not directed by the employer/agency. The fact that the WTBTS does, in fact, direct all matters in the congregation, nullifies all their claims to the elders being independent. "A rose by any other name, still smells as sweet," so to speak, or in this case, a Watchtower slave, by any other name, still stinks.