Or perhaps have the surveyors move it and stake it down with a flag and paint (on the ground and rocks?)
And have someone take LOTS of photos of the surveyor putting it in and where it is located (relative to other landmarks). Hope you won’t need to get a restraining order down the road…
In my area, I think you would probably just put in your disclosures that the neighbors leach field encroaches on your lot. You would not need to provide an easement. Then the next owner could have the issue fixed if they so desired. I am not a lawyer or realtor…
Any update? Was the vacation home in the path of the recent hurricane?