Well, those are old patchnotes. They are for Patches v0.1.001a(10.07) - v0.1.040Public(16.09) and unless the Spitter animations, mentioned there are a separate set of different animations as well as other stuff, everything is present in the game, except cheats. At least, I'm pretty sure group animations are not gated in any way in the actual version. They are just a bit tricky to trigger. Especially the 5P one (I believe, it's the only 5P animation so far), since it requires a specific order and timing.It's been mentioned here in changelogs and also many times in the discord server.
I don't use discord, so I have no idea what is being discussed there, by who and whether there is any credible source of information present there. People can say all kind of different things, doesn't mean those things are true.
There is a small chance I'm misrememberings things, so I'm going to doublecheck the 5P animation in current public version.