What if Kagari wasn’t actually a DNA made clone of Kurisu, but more of an artificially made person to resemble Kurisu? Leskinen had Kurisu’s memories the entire time, maybe he wanted to take them from an AI system he had created of her and give them to a what we know as Kagari so Kurisu could be a living human again?

Well, she could have parents, their is a possibility even if near zero, if it exists then it exists indefinitely, Final Theory - Alpha Possibility: Okabe loves Kurisu too much and does the stupidest thing he could possibly imagine with a lovesick heart and that's to go through the alpha worldline trying to keep Kurisu safe and Mayuri away from danger, change some thing, keep both alive long enough, make them stay away from the lab and far from any prying eyes, Okabe doesn't know of the Steins;Gate worldline because it doesn't exist at this time, in the end Mayuri dies an innumerable amount of times and soon all of her memories from other worldlines start to blur together, Mayuri confronts Okabe and tells him to let her go, not being able to coop with that he keeps trying to save her to no avail, comforting him Mayuri gets Okabe to agree to her plan, she dies and Okabe mourns longer then he ever thought he could, 11 years pass and Okabe and Kurisu whom just got married soon in 5 years have a child, Okabe has a secret he kept from Kurisu for a while and that's the fact that he and Itaru had built a working time machine, 10 year pass during which both Kurisu and Okabe die in World War 3 leaving Kagari an orphan, but Shizuha takes care of her for the remainder of that time frame, finds out about her father's and Okabe' s work and goes back in time, but because of this some other events happen that changes and deviates the Alpha worldline just slightly enough that the Beta worldline can finally start

Domino worldline effect:

Alpha -> Beta -> Steins;Gate

Alpha: Mayuri stays dead ( True Start )

Beta: kagari and Shizuha exist before ( S;G Achiever )

S;G: Kurisu and Mayuri live on, Kagari may exist soon ( Best End )

So in the end Okabe completed his mission of keeping both Kurisu and Mayuri alive while stopping World War 3 from existing and sern from taking over the world.

A better Question you should be asking is why Okabe chose to become a mad scientist and how the hell he manages to keep total sane through out all the shit he has or had to go through. Also the fact that while it may seem he's going through it only once you have to take in mind the fact that an endless amount of other timelines and worldline are going on at the same time. Ok, hear me out, new title, Steins;Gate Possibility Convergent, Okabe some how manages to get true link and all of him in any time/worldline now share memories and experiences as a collective, his mind gets destroyed worse than in Load region of Deja vu

Puts a whole new spin on MAD scientist.

And my theory would be that Kagari is Christina and Okabe's daughter and it basically reveals that all their efforts were in vain and they failed to avoid WW||| since kagari was an adopted child in the future with no parents and the situation was showing us that Suzuha and Mayuri are trying to save the world.. so I guess the same loop will happen again although in the last episode we saw that Okabe will succeed, from the first episode we actually have the ending already. I don't know if I have made my point here. Or I might have misunderstood this part 🤔 please let me know ur ideas