Evil is evil. Should it really be a numbers game?
In terms of principle and how you judge people, no. In terms of pragmatically how you act, yes. In this episode Saru said "Hey maybe we can avoid declaring war here with this clever technicality that we punished her." But she wasn't having any of that. Saru may have caused greater harm in the long run in this episode.
With Georgiu it's also a pragmatic question. We don't forgive her, but consider that her being around here may cause the least harm to the most people in the long run. She's a very skilled person whose interests are aligned with ours in desperate times, so we can justify working with her without having to forgive her.