Hagu, the author, has been very consistent in telling readers that manga Sasha is the exact same character as the doujins. She's done everything you've seen her do, and will continue to do so until he decides otherwise(he won't).
The ONLY difference between the doujins and the manga is that in the manga, Sasha never met, and dated Futoshi-kun(the fat otaku from the doujins).
There is some debate over whether he ever actually intended to make a more wholesome manga or not. It does seem like it started out like that given the rapid tone shift that happened. It's a pointless debate at this point however.
Also... I'M BACK MOTHERFUCKERS! At least a bit. Can't delete MangaDex accounts, so I thought I'd pop my head back in.
I definitely remember there being several different tweets on his twitter (Before that got shut down... For some reason... >>), where he just outright stated it was the same character but that none of the Doujin were cannon, only to later go back on that and say they were partially cannon, but not all of it. Now it's looking more and more like that was also a lie?
I'm also pretty sure there was a few instances of Hagu actively having to make a tweet about how he was changing the story and that it wasn't going to be the same cannon as the doujins because the editor got pissed about it, only to later flip it around and say "Ha! Gotcha, it's the same!" (Obviously not like that of course)?
Yeah, one can argue "It's not the same because she never met this one character from the doujins!" and they'd be technically correct, but that isn't the part that has so many people up in arms about this series, both online here, and actively in Japan. The part that people are so pissed about is the blatant bait and switch of the early volumes, coupled with the just straight lies early on in release. Sure, he may have been open about it being the same Sasha from the get go, but he definitely said the doujin weren't cannon in the early stages of release, only to just outright change that later.
If I'm completely honest, the only way Hagu could win anyone over at this point would be to just have the MMC wake up from that dream in the end of Volume 2 (3?) where he saw Sasha with that one guy at night, and say that everything in the series from that point to now has been the MC's wild fantasies running amok in his dream, and that the doujin aren't cannon to the manga. But even that probably wouldn't work for many people and would likely make people even more pissed...
Really it's all just a lose/lose for Hagu at this point in my book. I can't really see this working out for him in the long run...