Mistakes in the Harry Potter books

You know the article Mistakes in the Harry Potter series? Let’s add Umbridge >:)

Theory: Voldy made Quirrel come back to life or something?? But this is still a MAJOR flaw for Universel

I u dont belive this is the real thing, look up YULE BALL QUIZ on Wizardingworld.com to see proof

In the second hp book, harry,ron and ginny hold onto Fawkes the Phonex to fly up the pipe slide.

In deathly hallows, ron and hermione go to the chamber to get the basilisk fang for horcruxes

But there is no way to get back up

Technecally, Ron and Hermione would've been stuck in the Chamber for the rest of their lives

(Moderator Edit: Removing an interlinked Wiki; advertising a post)

I've been rereading CoS, and I've reached the part Harry killed the Basilisk. Since the Basilisk is a living organism, and it died, and Harry watched it die, Harry "witnessed death". So, he should have been able to see the thestrals.

Still, he couldn't see the thestrals.

Why?

I understand why he couldn't see the thestrals after his parents or Quirrell died. But no one talked about the Basilisk.

On the page about mistakes in the books, for the chapter 'the Midnight Duel', it says that Charlie might have left the Quidditch team before 7th year, but he was captain. I don't think a Quidditch captain would or could leave the team.