From what Tyrone could tell, no one but him was seeing that Officer Chase was different. Apparently, they thought that it was normal for her to be black. And that's what she was now, by the way. Her transformation was not yet complete, but she was most definitely black.
Also from what Tyrone saw, Danielle herself didn't seem to notice anything different either. She looked down at her hands more than once. Seeing the dark skin tone should have alerted her, but she apparently thought it was all normal.
She kept typing, continuing Tyrone's processing.