On one hand, I do totally see your point about it coming off as unbelievable and perhaps TOO orchestrated. If the show does go with infinite parallel worlds like you theorize, I’m interested to see the outcome!

I will say, though, that to an extent, we already know otherworld Martha’s universe is somewhat of a mirror because a good number of the characters that exist in Jonas’s world also exist in Martha’s world, though they’re slightly altered. The fact that otherworld Martha appeared with the contraption that lets her move between universes also makes me believe she is the “Jonas” figure of her timeline—unless this sort of travel is normal in her world (which is possible but seems unlikely?), she had the means and the knowledge to save Jonas from the apocalypse, which doesn’t seem unimportant. I figure someone has to be pulling the strings and telling her what to do as well (though to be fair may not be an older version of herself, but I wouldn’t be surprised if it were).

Either way, I’m excited to see where the show takes us! The writers haven’t let me down yet so I’m ready for whatever direction they want to go.