The Janitor that they mentioned whose identity was unknown and missing is the Older Brother. I think someone mentioned the brother MIA in the story as of now, but MC took his brother's place and be the brother of Mini MC version. Also he looks a bit like his brother when he grow up, so it doesn't actually affect his mini version much.
That's why MC used the Janitor's Identity. I think it was the Janitor who leaked the lab location in the first timeline but somehow that didn't happened in 2nd timeline, he was probably caught?? Not sure but due to that, MC was able to use that Identity to fool the Team and due to his looks closely resembled his older brother, was capable to fool his Mini Version.
As for the timeline, he did regressed but because something shouldn't happen, happened the timeline became alternate. Therefore, he is from 1st Timeline and he is currently on 2nd Timeline with too many events that has never happen in 1st Timeline. This is just a theory, I think his Older Brother was really dead in 1st Timeline after they discovered MC's Lab Location because it was the brother to leak the info to the Adopted Father's Team. Meanwhile in 2nd Timeline, it is possible that the brother got caught leaking information and was kill? Because the Janitor who suppose to deliver the information was MIA (So we have no idea if he die or not until novel reader spoiler us), MC took the advantage to act as the missing Janitor. I think in the end his mini version suspected him but chose to stay silent?
Fascinating how you explained it all so clearly and now I'm having this thought of the butterfly effect he caused since the very beginning he regressed...
Could it be that his real brother became MIA because he "took" his brother's name hence the brother in this timeline getting erased? And not his younger self? Like from what you said, 2 same existence shouldn't coexist in the same timeline but because 1st timeline him unknowingly "stole" his brother's identity that's why it's the brother that got poofed out of existence? Since from all the novel readers just said the real brother got MIA but no further explanation..
Just a theory that popped up in my mind lol
Anyone can explain or give me spoilers why is it possible for two identiies (MC) to meet? Since usually it's no possible or not allowed in fear of messing the timeline.
How about MC's real brother? Is he still alive and they will meet soon? Or maybe he's actually someone MC knows?
Will mini MC realize that 'Woo Hee Jae' is actually the older him? If he will, what kind of reaction did he give to MC?
Sorry, too curious to even start the novel (if it's an adaptation), I need a motivation to read it by knowing the answers for questions above