They have. Alex directed the sequel to the Wine Party sketch, the Bill Griefer stuff/The Three B's of Business, and some of the Vsauce parody stuff that was dropped on the HydeWars channel after the boost from the iDubbbz doc. Forgive me if Alex has filmed anything else with them, but, yeah, he's worked on/off with them the last few years, and his production quality is top notch. A more than worthy successor to Andrew Ruse, absolutely go check out his stuff. "A Profoundly Angry Young Man" on his channel is a work of art.
To my knowledge, Bobby Hacker was originally supposed to direct WP2 (Sam stated this in an early stream), so I wonder what changed or if Hacker is just assisting them in production. I know Hacker has helped with some MDE stuff in the past also.
Yeah, that account you mentioned was Friko, who from what I remember worked with the Fun Church guys a few years back, of which Noah was one of the 3 hosts. Noah still works with Mackenzie Becket I think, and she was the girl in question. As Friko stated a while back, Noah's always been a huge MDE fan, to the point you can literally see How To Bomb on his desk in his Poker sketch. I know the Fun Church crew printed out custom World Peace and Alienmode t-shirts (unless Sam/someone sent those over - honestly might've been James Price, who Noah (and Charls) still works with), and were all huge fans of MDE. Shout out to Fun Church, rest in peace, that was some good stuff.
Not sure where most of those guys are at now ever since American Odyssey (their content group) broke up. I know Ben Lunato makes some sweet conceptual video games these days, and Noah's still making content, albeit shapeshifting it into even more of a unique style with every new video. Either way, I'm sure if Sam asked Noah to cameo in WP2, he'd probably do it. Hopefully that happens, would be cool to see them finally team up after years of making similar content. Should have Noah in a sketch where they dress Nick up in a Dan Schneider fatsuit and Noah kidnaps him and hacksaws his feet off.