Tenohira Kaitaku Mura de Isekai Kenkokuki ~Fueteku Yome-tachi to Nonbiri Mujintou Life~ - Vol. 11 Ch. 62

[KuroViLolitannia]

I dont get why they would agree to the last part.
The whole point of keeping the guardian saint "hostage" on the island was so the Temple WOULDNT attack the island OR release the witch in fear of killing the saint.
So to disregard that, and allow the temple to think the saint guy is NOT their hostage, would allow both those things to continue, its like...
What did this negotiation actually accomplish???
it's not like the church will uphold their side of the deal of even recognizing the island as a nation now, they have no reason to.

The plan all along is to get Rukia on their hand, getting recognized as a nation, and then blame the church for "taking action first by sending assassin".

This way they wont be able to be blamed by the church for kidnapping Rukia because she was given by the church, proofed by the church acknowledging them as a nation, and won't need to return her in the future because the church is sending assassin for her anyway.

And most importantly, hiding MC as the true leader of the nation and Rukia's family, preventing the church from blackmailing him.

Even if they are not recognized as a nation, the most important part which is saving Rukia and hiding MC is still accomplished.