Trust me, that concern is unfounded. While he may in fact be one of my testers, I am most certainly NOT stealing his work.
The truth will bear me out here. Let me explain...
Devan is alive. So what? Isn't that like, the #1 universal truth to many JJ2 episodes?
Alternate reality. I am not quite sure where you are coming from, as EM's episode is not [that I am aware of] in an alternate reality. His work resurrected Devan, in mine Devan was never dead.
Trilogy. Big deal. Lots of people make [or plan] multiple episodes. Take FOD's War of the Rabbits saga. Or the Tomb Rabbit adventures. Or Sonicnathan's work-in-progress series of stories. It's not unusual to make 1+ episode, nor to plan one.
Galactic War. ?! That concept belongs to Epic, NOT Evilmike! Rabbits and Turtles are already warring, so that's completely silly.
In short, I cannot think of any real ripoffs from Devres [that you mentioned, and that I remember from your notes] that I have employed, except maybe that you are supposed to use jazz...
Thus, your concerns appear validly, but unnessecary. Thank you for raising the question though!
And yes, I think the musics will do quite well.