The True Light group is also said to be extremist. So taking the view point of the enemy of my enemy is my friend might be why they would have such an apparent alliance. With both groups keeping a wary eye on the other. Right now the Federation is the strongest force in that area of the universe, so it would make sense for the lesser factions to join forces against the foe they couldn't stand alone against.

That, and who knows, it could be some manipulation by the Undine too.

This about sums it up.

Idunno, some arguments make some sense in the Cardassians trying to get strong or a faction of them, but wouldn't you ally with ones that didn't try to make you go extinct? There is many other Alpha quadrant potential allies like the Breen.

I would also argue a small minority of Jem'Hadar ever break ranks, they have safe guards in place to make such things rare such as genetic coding to worship their changeling gods, the order of things and addictive dependency on a drug which also will kill them if they go too long without. Yes there is the one episode where a single JH soldier was freed from it and started to think rationally but it also showed that was practically unique. Never to get large enough in numbers to be a threat to any real power like the Federation or Klingon.

Anyhoo, this is not a rant or anything just a discussion on why I think there should have been a different ally... besides there still can be a few hopping over from the gamma quadrant with their own agenda, the few you encounter inside the worm hole and then a good potential to really face them in an expansion that we can use that work hole to explore there... and them to invade...

Cardassia post Dominion war is kinda like....fallen USSR, an True Way would be like ultranationalists. Mission threads along this the True way storypath do reveal some reasons why it makes sense for JemHadar to be working with the cardies again, tho i won't spoil it for those who havent done it yet.

They are the Al Quaeda and Taliban of STO.