Board Thread:Episode Discussion/@comment-25396609-20191207154319/@comment-24994749-20191211150435

SpiritedDreaming wrote: And she can tell Robyn that it was a frame job, since she's also a Faunus and presumably has nightvision like Tyrian. She very clearly saw Tyrian.

Even without night vision, she should have been able to make out that wasn't Penny.

And, of course, is both her and Robyn heard Ruby tell NR about Tyrian, and saw their reaction to it.