No, not really, because if you look at it from my point of view, disney owns VMK, Hosts work for VMK, so, hosts work for Disney...
For example. Disney owns ABC, so, ABC employees work for Disney.
what the Hosts are NOT is cast members. Cast members are park workers. Be they people who play charachters or the guy sweeping up the bathroom. The people who make the movies are not cast members, although they are Disney employees.
What might be a possibility, is that the hosts are per diem workers, meaning they are subcontracted to work on VMK through a thrid party company, like sulake.
I once worked for a company that subcontracted me out to work for Microsoft, while I got paid by the company that hired me, I still worked for Microsoft and was bound by their rules of employment.