Do you have Shuichi's French talent intro? Considering you uploaded all the others (except later-game ones) and there's a dead link on Gallery:Danganronpa V3: Killing Harmony, I was wondering if you accidentally skipped it or something.
Hey there! Unfortunately no, Re:Birth will never be an official game nor even a fangame. :( However the creator, Miwashiba, has been making videos (as you mentioned) of the first trial! Though they are ONLY videos and not playable demos or anything like that. And there likely won't be any more videos after the first trial. You can however find some text information on the lore of story on the Tumblr right here!
I see many characters' blood types come from their DR3 guidebook profile, but does Yasuhiro have a profile page? I don't see one on the wiki, but oficial material seems to consider him part of Future Arc's cast equal to the killing game participants, even if he wasn't technically part of it.
I know it's not on the wiki, but that doesn't mean it doesn't exist. None of the staff have the DR3 booklet so we can't exactly check at this time. Since the information is also minor it's not too top priority to ask around for now.
Please understand that it takes time to be able to locate the files that I have extracted, it is especially harder since I am the only one who has the files for V3 and I am also very busy in my actual life. Not to mention that there is a large abundance of files in there.
I see that you deleted the old objecting sprites from V3 and replaced them with separate ones for Non-Stop and Mass Panic Debates. The new ones are cut off on top as they are in-game, but shouldn't the old ones still be there if they're from the game's files?