I don't know if I am going to work with a studio, a distributor, a production company or something else. But I would like to be prepared, as apparently it can be hard even for studios or networks to get visas -- the producers of the Lost TV series had trouble getting the proper visa for Evangeline Lily (a Canadian citizen), and they finally got her an O-1 visa just days before shooting her scenes for the pilot, after principal photography had already begun.
I remember reading remarks somewhere to the effect that "Management Consultant" was an intentionally broad category, which could apparently include "independent producer".
The studio, when it pays an independent producer for his services (which are to bring together and manage outside material and talent - scripts, actors, directors - and to generally make a project happen), it is actually contracting the services of an independent individual. A producer is essentially an independent contractor, which is how NAFTA defines the "Management Consultant" TN occupation category. It is also temporary work (the contract only concerns one film) as opposed to a permanent employee, which is a requisite of TN status.
I would like to know for sure if that would in fact be accepted for TN status (if presented with the contract from the studio or production company of course).