In writing terms, it's called a "Chekov's Gun". It goes something like this, If the writer mentions a gun, it will be used later in the story, in whatever way.
In this story, the gun is Melissa. If it wasn't to make her be alive, there was no need to mention the absence of her corpse. Moonbox knows this. So, it is still his prerogative to decide where or how to use the gun he loaded, or even if he uses it, while that is considered bad form, it is still within the realm of possibilities.
So, all we can do is: #SaveMelissa
Peace