...That would be insane. Some serious bullshit would start going down in the swamp of death. Suddenly the whole swamp remembers being killed by Leaf and Mist. And they don't remember us being killed. We would have to keep everyone in the swamp from knowing that we fled while they died. And they would likely try to prevent our "suicide". Jiraiya would kill everyone all over again just to get us out. And if the swamp learns about that...
Also, what would Zabuza do?
What would Yagura do?
What would the Akatsuki do?
Kagome would be impossible to find.
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Speaking of which, we need a rendezvous. A "everything has gone to hell, and we can't go to Leaf" type of rendezvous.
Have Mari say she has a cunning plan to get client state status with Leaf. She meets up with Jiraiya, confirms that he remembers everything too, and he allows Swamp to be a client state in exchange for Leaf getting Mari, Hazō, Noburi, and Keiko as hostages/diplomats.
Jiraiya and Naruto form the Gōketsu clan, then adopt us into it. Send the team to find Kagome and bring him back, if he is still in the forest waiting for us.
Ren will know that Yagura will find out who his replacement was sooner or later, and probably won't want to stick around long once he does. We can get her to defect along with Hana, and keep Hana faaaaaar away from Mari at all times. Adopt them into the clan, get them to immediately start training sealing alongside Hazō.
Pump out all the skywalkers Leaf can. Start pumping Hazō for WMD ideas, especially sealing ideas that would work well for Naruto. Make sure Naruto learns a suicide jutsu so his clones can just explode themselves if they get grabbed by Akatsuki.
Start negotiations with Akatsuki, hope we can convince them to try a less violent path to peace. Uplift, maybe.
It was my off and on campaign to get us to contact Orchimaru. We still should figure out a place to bounce to if things go terrible. Isan is probably out and with Oro "dead" can't join him. Our best bet is probably to defect back to Mist
I fully agree with having a contingency plan. But I don't think that anything that is a landmark of any sort is a good idea. How about instead we pick some random place that no one else knows about? Maybe the forest where we met Kagome, or the beach we hung out at once? If we all have skywalkers we should be able to avoid leaving a trail that anyone other than Zabuza himself could follow. Whether that's sufficient would depend on whether he's still alive or not though.
Also, lighting a forest on fire again should be good enough to throw any Inuzuka off our scent even if we don't have skywalkers.