Thats actually how I read it.
Consider this is the "Second Apocalypse" which in itself is self-negating. You can't have the end of the world twice

.... But if you can have a 2nd apocalypse, then that implies that "the end of the world" already happened once, is happening again, and can happen a 3rd time, and on and on.
Because of this, I read it more along the lines of "the world will come to a place where it may end again, when an Anasurimbor returns", and further that "it will only end if, and only if, Seswatha truly dies".
If you read it otherwise, more like "If A then B", then: an Anasurimbor will return, Seswatha will die, the end of the world happens.
Another consideration is that the Celmomian prophecy is entirely false. The Consult mention that they know something of true and false ...
Just thought of the fact that there is no out for Seswatha in the Prophecy. No mention of the world surviving if the Inchoroi are wiped out, etc., just that when Seswatha dies, all is lost. Again, the end has little to do with anyone, even the Consult and Anasurimbor, than it does with Seswatha. Doomed to live forever lest the world ends.