[It's extremely unlikely that] Eliezer or someone else who looks like a crackpot will actually save the world

This is ambiguous.

The most likely parse means: It's nearly certain that not one person in the class [*] will turn out to actually save the world.

This is extremely shaky.

Or, you could mean: take any one person from that class. That one person is extremely unlikely to actually save the world.

This is uncontroversial.

[*] the class of all the people who would seem like crackpots if you knew them when (according to them) they're working to save the world, but before they actually get to do it (or fail, or die first without the climax ever coming).