I agree that those two Tieflings are would-be lynchers. They're just going to kill Lae'zel based on hearsay from an absent friend.
There needs to be a line of dialogue where you say Lae'zel's with you and isn't part of those other Githyanki, let her go. Or, better still, just like in the grove with Kahga, our paladin states we're versed in justice and will decide Lae'zel's fate.
And knocking out needs to be acknowledged with a not-killed state.