This can't be the "special" task though. He doesn't need a 2nd rig with two 3090's for hosting purposes or some simple coding and update testing. And it doesn't explain why he's hyping this whole thing up like it's the coolest addition to the game his Patrons have ever seen. In his statements, L&P is literally saying how thankful people will be, how awesome it's going to be, and that it is sooo worth the wait and update delay if it works out the way he planned it. No Patron cares about a login mechanism in-game. If anything, that just makes it more tedious. And, all that aside, it wouldn't make any sense considering his statements about this new addition.
I'm also having trouble believing that it's somehow about DLC content made by several other developers. L&P couldn't even find a single developer he deemed worthy to work on the game, and now all of a sudden he contacted multiple developers to work on DLC's with him? Unlikely.
It can't be about writing, coding or testing either. The only things one would need a 2nd powerful rig for while also contacting multiple other developers, are either animations, or scene creation. But there's something that, atleast to me, doesn't add up. If you delegate this task to multiple other developers, why would you need a 2nd powerhouse of a computer yourself? L&P didn't talk about an actual lasting collaboration with other developers, he's only mentioned a special task. And judging by his statements so far, I don't see this being another developer working next to him on the new rig either. It has to be something we'll be seeing in the game, so I'm thinking it might be animations in the end, and the developers he contacted might be working on a script for his animations or whatever else there is he would need them for.