Hypothetically speaking...

If I were planning on writing a most definitely non-canon story in the ending verse... what are the rules on that? Do I need to pass it by the original author? Give him a few ideas of what I'm thinking?

3800048 I only went to him after I'd posted and had it approved.

3800048
Now, I know that is is incredibly late, but here's my rule.
Just go ahead and write.
All that is required is that Jason is a main character. He doesn't even have to be the main character.
Other than that, just make sure it's spell checked, grammatically correct, and in the universe.