That was my thought. So after this round two people will be voted out. One on each tribe. That leaves us with 14. The only person we publicly know is safe either this round or next is you. So one possible solution is to assume the immune person over there does not jump ship.
If you were to volunteer to munity you are guaranteed to survive at least one round which might be enough for a true swap, which given how open you have been about sharing information with us I trust us to want to protect you assuming we swap at 14.
This would mean that most likely the person who swaps here won't be the immune one. If they are we can't help it and just have to bite the bullet, but they are pretty broken after the 5-3 split. So the odds are the person with immunity won't want to go anywhere. Most likely we could potentially take two of them out and set us up to be safe in a swap or merge scenario after.
Again this hinges on two things:
1. You are willing to go over on the hope that either a swap is coming soon, or that you can survive a round bluffing you will use the immunity, don't use it, and then use it the next round if we don't swap.
2. The rest of the tribe stays strong in voting out whoever they send over. If that person is the one who has immunity, then whatever we can't help that and were going to have to vote someone out anyways.
This is an option if we want to try to survive together, but if not I will drop it and we can just do what we were going to do individually. I just wanted to throw it out there as an idea.