I saw that the mask changed and she just gave in to her wish to come back to live in her last 'test', so I think she was sent to void, but I'm not really sure. Can somebody explain, please?
Firstly, in episode 11, in Ginti's bar, when he sent Harada and that girl, it was shown to be the reincarnation mask, but soon enough it changed to the void mask. We can always see the reincarnation lift is on the left and the void lift is on the right.
Decim sent Chiyuki to the elevator on the right which is usually the void one. However, there was a reincarnation mask. Here comes what happened in Ginti's place: he switched the masks. Probably Decim would also have done the same.
Well, the mannequin, regardless of whether he sent her to void or reincarnation, he merely made it for remembrance.
She was sent to reincarnation. Why I think so? Because we could get to see the reincarnation sign over the elevator, right after it closed.
About the mannequin that was shown later, it was, I think a fake one that Decim made. I am a little bit confused about that, but if we think that she was sent to void, then that sign over the elevator would be shown to be kinda meaningless.