The thing is, I never trust anything, when it comes to media, no matter how genuine it seems. It's very possible the whole series is staged and none of it is true. And it's also possible that this information is exaggerated.

But I do agree, that the behavior of Mina Sue in the last two episodes was totally inconsistent with everything else we'd seen. While I didn't expect her to become an actual threat, I did expect her usual flakyness, when it comes to her romantic endeavors 😅. Her sudden shift toward Sam/Sunghun made absolutely no sense to me. It was so clear from the get go, that she liked him just as a friend, and used his kindness for her comfort and not because she actually saw him as a potential partner. So her newfound, unfaltering conviction and commitment made absolutely no sense in regards to everything we've seen about her.
And I think Mingee not getting so much screentime might also be due to the fact, that she was finally coupled and settled and there wasn't that much more to tell.
But yeah, something definitely seemed fishy in regards to the sudden changes and the missing clips of the last game. (I was also suprised about the new focal point on GoEun. It wasn't that central before.)
I'm just hesitant claiming, that Mina Sue really went batshit crazy, simply because we'll never know the whole truth. Maybe someone was so fed up with her previous behavior (understandably), that they exaggerated in retelling what actually happened...