She lied very poorly about what she did when she woke up in th outside world. She said it was a boring apartment when nothing to an innie would be boring, everything would be new and interesting. Also the night gardener deal. There is no such thing. And then her behaviour was off, she was beyond mean, she was cruel. And of course who else would have the power to do such things?

at the same time, I think Harmony figured out ( in the car park/building entrance) that Helena was acting as an innie, that’s why she got spooked and ran.