[SPOILER] What you think about red?

[Thaliur]

Also, I've read most of the posts on this topic and think that red isn't dead because if he died.  There would be a body.  Not some little speck of Gunpowder

It could be possible.
We don't know the temperature inside that incinerator.
If this device was really used to dispose of "experiments", I could imagine quite a high temperature in there, since they would want their "experiments" to get completely annihilated.
So it might well be enough to even reduce bones to ashes, or at least destabilise them so they shatter when the big drawer moves.