Seems to me like the memories he’s been shown are of past timelines, so in timeline number one he died first and in the second timeline he lived but the other one died so they turned time back again and that third timeline is the story we’re reading right now? Sorry I struggle remembering Korean names, like I know who is who from seeing the name but can’t remember them off the top of my head
spoilers!
they're in different timelines - they used the watch to turn back time
in the first one (the one shown in the recent chapters), MC lives and ML dies (ML didn't awaken if I'm remembering things correctly)
in the second timeline, MC dies and ML lives (the one we see in ga-eul's shards). we'll eventually get to see what happened here (they had to act it out in a dungeon) but it might take a long time before we get here lol
the current timeline they're in is the third one
there are consequences every time they turn back time that's why the situation in whatever timeline they're in gets worse the more they use it

I didn't understand this chapter at all