Having a justification for breaking a truce that is not covered in the truce and that still flagrantly breaks the truce is still breaking the truce. If Taylor and/or Ammy agreed to waive any punishment due to agreeing that maybe there was reason enough to do so, that's one thing, but that's not the case here. It was simply ignored and forgotten about.
Like, when Oni Lee saved Dinah, that could be considered forgivable without comment, because Oni Lee was defending the truce that Coil's mercs broke, even if, at any other time, attacking and/or killing people on neutral ground would've been a major breach. But that's not what happened here. Abducting someone off of truce-enforced neutral ground with the threat of violence is not okay, and that's a separate issue entirely from the ABB Local 433 pressing minors into service, especially those under the Miko's (and thus the Okami's) protection (which is what Taylor took Lee to task for).
It's okay for Lee to defend the truce by defending Dinah from getting kidnapped off of neutral territory, but it's also okay for Lee to kidnap Yuuta off of neutral territory? What?