Facts About My Little Pony: Friendship is Magic

Fact 18

Do you wonder how Sunset Shimmer knew about Twilight Sparkle and
her Crown?

We all know that Sunset is in the Human World when Twilight came to the Crystal Empire.

But how did she know that Twilight has arrived if Sunset is inside the Human World?
It's easy, the only Suspect who might tell Sunset is Flash Sentry.

I know you think that it's impossible to be him but the Truth is it is Flash.
To give some proof:

Notice that when Twilight asked Cadence when she saw Flash?

And Cadance answered that he's a new guard. It's the first series when Flash showed up then he's actually new. So it might that he spied at Twilight and goes inside the Portal
where Sunset Shimmer was.

All of us already knew that Sunset just used Flash to be her boyfriend so she will be famous and popular in school. Maybe she also manipulated him completely.

So maybe it's true, because how did Sunset made an exact copy of her crown when she will exchange it while she's sneaking to Twi's room.

So perhaps after the Princesses exits the Throne room, Flash sneaks into the Portal and goes inside and told Sunset everything.

So what do you think?