I'm saying that my opinions on Khemjira being aligned with so many other people means that I'm sincere about my views and that I'm not trying to troll you.
Uhm... Everyone was powerless against the Killing Curse... except for a baby wizard. Yet I don't see you screaming "PLOT HOLE!" about the Harry Potter books.
I'm sorry, but the answer to that question doesn't actually impact the plot in any meaningful way. It's not a plot hole if an author doesn't explain every conceivable thing that pops up in your head.
"Lily and James Potter were aware of the Killing Curse, yet they had no way of stopping Voldemort from killing them because... it's in the script." I think you love making mountains outta molehills.
When Khem learned about her past, all he felt for her was empathy. Maybe his previous lives also felt empathy upon learning about it, enough so to prevent them from feeling resentment towards her. Makes sense to me!
Those spirits weren't as old or as powerful as her. Duh!
Maybe because they didn't have any resentment or grudge holding them back from being reborn. Makes perfect sense to me.
She's a ghost, you can't kill something that's already dead.
She literally begins her path to rebirth in the final episode, thus automatically disproving your entire point. So what if it took centuries for her? Not everyone has to be reincarnated in the same amount of time.