Hey,
So I know this is coming to you three years late, but I came across this thread while searching for a Sun save file to download and took a crack at solving your save file issue! I used a combination of HxD and PKHeX, and comparing a working Sun save file to yours and the issue appeared to be a combination of the in-game "Last Saved" time and your character's overworld coordinates. I edited both and when loading the edited save in it did the trick!
I've attached the working file and some pictures so you can see it up and running! Again, I know some time has passed since you initially posted this, but I hope you can get some fun out of this file again. I'm sure Birbo and the rest of the team have missed you too!
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