Franz used his eyes on the root sac, however, the little creature inside the sack was already dead as there was no fluctuation in it, even with Tempestas who seemed to have no mana, he could still see his emotions and desires through his eyes, however, it was not the same with the little one in front of him, so it is most likely that he would have already died a long time ago.
Perhaps the wooden guardian was ignorant of the fact that the creature he was protecting could no longer be born or it was simply impossible for him to accept it, it could also be the case that he simply couldn't attack the one he was supposed to defend even though he had already failed at the task.
That may also be the reason why the guardian was angry.
