No, it is not accurate. That guy's posts, and the replies advising his information was incorrect, have all been deleted.
So:
- NTR - No, nor is there any indication of it.
- Gangbang (past or present) - No, nor is there any indication of it.
- "Slut/hoe" - The bit about this was the only part with some accuracy to it. There is one LI who gets corrupted by the sorority, and in one scene, you see her coming out of a room at a party with cum on her chin. This only happens if you "reject" her, by not saving her from the sorority. At that point, she is no longer an LI or possible LI, as her path has been closed. If you save her from the sorority, this scene obviously does not happen, so yes, it is totally avoidable.
Regardless of what they do or don't do though, all LIs are also avoidable.