Here you go:
www.shadesofgreen.org
You would probably need to dig though all the records to be sure. There's going to be a lot of nuance to this.
From the link:
Which at first glance, sounds like Disney owns the land and MWR owns the stuff built on it. Which one pays the District tax bill is probably very interesting.
Either way, it's why most posters say "majority" or "most" or "primarily" instead of "Disney is the only taxpayer in RCID". To avoid an over simplification and absolute. By percentage of RCID taxes paid, Disney is clearly the majority of them by a lot.
*Edit - By "interesting", I mean full of legal details, contract law, and subject to lots of conditions of the contract on how the relationship was created. Not some fancy plot point. Also, probably only interesting to an attorney or accountant and extremely boring to everyone else.