Place her stuffed corpse on the quest bed, then die?
The corpse is already gone. Sort of. But if she would rise to god tier then she'd combine with Jadesprite, inheriting all of Becs powers. Which is quite god-like (and really, she needs the power boost considering how far behind the rest she is)
Place her stuffed corpse on the quest bed, then die?
Impossible. The corpse is now gone, having been prototyped.
Place sleeping Jadesprite on quest bed, die.
yeah, like this.
If you'll read the post I made a bit further up in the page, you'll see what I thought of this already.
To rephrase: I don't think that's possible, because even though Jadesprite now inherited attributes and characteristics, she is still not Dream!Jade or an analogue that is satisfactory enough for SBURB to use as a Dream!Self in the God Tier process. One tell I think would be the fact that she does not become Jadesprite in her sleep.
Another perspective to look at this would be from the game's perspective: It wants to generate as much excitement and general conflict as possible, and though the Bec Noir thing was barely acceptable because of the drama, a Jadesprite wouldn't (or would it?) be acceptable, because it would be a conflictkiller.
Hussie deals in symbolism however, and it would be interesting to say the least as it would continue a trend of duality already within the comic. Then again, it already does (Jadesprite|Bec Noir), but I'm not going to eliminate this option entirely yet.