Dec 11 logic error?

https://cluesbysam.com/s/help/308099a6a9c6?state=UhoQ-ABE8AAA%3D-080

Ruth has a total of 6 innocents. 2 of them are part of row 5 so we are left with 4. Zara's clue limits that only Logan or Martin is innocent. So we have 3 other innocents: Katie, Olive and Sarah, but the game doesn't allow to set Sarah to innocent.

Where is the error?