For some reason, it seems that the doppelgänger's plan isn't working on Rey. Rather than wasting time speculating the reasons why, she starts to approach 'Carlisle' for another strike--

And then a challenger appears.

No doubt either the 'tool' that the double was looking for, or an ally like the many others here.

"Are you k--" Rey stops herself, taking a step back before flinging a hand at the imposter behind Shadow. "He is fucking one of them."

Whether or not Shadow will believe her because of his own bias or because the doppelgänger's influence has more success here than it did on her, she'll find out in a matter of seconds.