I’ve come across your discussion concerning Doncic’s growth and overall height and I just wanted to offer some layperson insight.
I did some digging on his parents and his father, Sasa Doncic, (used to be a pro basketball player) is listed as 6’7.5 on his Wiki page. He used to play SF/PF/SG and seemed to be rather strong and athletic (for 90s era Euroleague player with poorer conditioning).
I don’t have info on his mother, but judging by the photos where she’s standing next to Luka, I wouldn’t say she’s shorter than 5’10 either (assuming she’s not wearing giant heels?).
Doncic also used to be listed as 6’6/6’7 frequently about a year ago, but is definitely a solid 6’8 now, so he has definitely grown in that time. Another thing, I don’t know if it’s just me, but if you disregard his overall size, Doncic still seems pretty teenaged looking, especially if you compare him to other players in the draft who basically look full grown at this point. I don’t know if it’s the extra pounds, or the "baby fat" some have mentioned, but he still seems to have some physical maturing to do. I’m far from a growth specialist and I'm not saying that he WILL grow some more, but he was still 18 less than three months ago, so I think he has potential to grow at least an inch, plus there’s a possibility he’ll still naturally get a bit stronger thanks to his father’s genetics.
(Note: Edited by moderator to remove photo-failed-to-load errors. Poster is welcome to try again, perhaps inserting a link instead of uploading will have a better chance of success.)