I know it's not the following:
Andrew Tate - He's a "pimp", too many conflicts with his "pro sex work" stance that would result in him looking even more retarded. Bad optics that he's a boxer too. The mental concept of Ian getting beaten up in a boxing ring by Tate isn't something that he would like to have out there. People would be beging them to be in CC3 and neither one wouldn't do it.
Sam Hyde -
Already mentioned it, ship already sailed.
Froggy Fresh - Old news, insignificant and a snoozefest. The Jomhas want more money than what such a video would generate.
Kiwi Farms - I joked about it, but I don't think they want this thread to have normie attention. Would be the funniest pick, but unlikely.
Asmongold - Too much of an odd choice since we got cr1tical, xQc and the rest of the Twitch slop gang doing the same retarded content. In that case a more fitting choice would be Twitch or Kick as a whole, but he got too many associates to burn the bridges there.
More likely:
MrBeast - Big chanel = attention, easy to "puch up". People already done a few attempts so he knows what backlash can occur.
Keemstar - Nostalgia bait. Boogie and WingsOfRedemption are easy to make fun of too.
Elon Musk - His
latest video sure hints at him not liking Elon and some political figures on the topic of trolling and memes.
Some political figure - see my points on Elon above.
Ethan Klein - I want to put this in the unlikely category (due to their previous friendship), but Anisa is too much of a bitch on the Palestine vs. Israel thing and can convince Ian to be even more spineless. Can't rule this one out.