I would say the greatest threat of them all. Vivek is a jeet, and you can tell he's a jeet, so every time he opens his retarded jeet mouth and demands you let him import infinity jeets, the lizard part of your brain is telling you he's not doing it for your benefit.
Elon is more difficult to nail down - I would assume his motivation is purely economical, but he does have an Indian halfbreed child, though it's questionable how much of a fuck he gives about his progeny, considering he's got a dozen of little race traitors running around.
Vance, on the other hand, only has one woman (that we know of) in his life, and has had two children with her. I would assume he cares deeply about his two little turds, so even if he is not outspoken about his preferences, his main motivation will always be to do everything in his power to ensure his progeny have every advantage they can, which makes him a natural opponent of an all-White America.