nope
and you got the reason right
Hmm... Ima use gardendless as a reference point for this idea, but considering that when spawning a boss in gardendless sandbox, killing them doesn't end the game, and they do their outro animations automatically, what if you made a separate version of the rogue reactor that DOESN'T end the game when killed and despawns after dying? Bonus points for never telling anyone that it's actually a whole separate enemy code-wise