I don't THINK it's been specifically mentioned so I'll chime in to say if you take Sazza to Minthara which will cause Minthara to automatically start the raid, you can still make her temporarily hostile after the dialogue as long as you pick the dialogue to let the raid go ahead. She'll start walking away as she normally would when starting the raid but will still become Temporarily Hostile as described in the instruction post. Just don't let her walk too far before initiating combat so that nothing unexpected happens. And it's probably advisable to kill the other two leaders before leaving in this case just for quest safety.
