" due to their involvement with religious extremist groups"
You keep saying this, I've no reason to assume that's the reason they contacted them.
"we don't know why they happened."
Would that apply to winnie the poo and similar things?
I'm don't get this hand waving around 'we don't' really know why'.... is that supposed to make it ok?
Sure you have no reason to believe the extremist thing, but then, the explanation you've proposed leads to the Streisand Effect. I find the former easier to believe.
As for "Winnie" - that's much easier, you can just grep for the phrase.
The "we don't know why" basically means we can't assume things, especially in this case, where there's a fundamental language barrier and ongoing propaganda war.
As for the bans - we don't know why they happened. Claims it's related to discussing Tienanmen are just that - claims.