Zara's idea wasn't bad, other than the fact that they didn't know how to do any of what she said. How to find a ghost that can help them enter another time and dimension and how to have them help them with these two high voltage bars on their way to find their father.
One week has passed since the new information Zara gave them and Merlin was still staying in the hospital bed. Merlin was devastated after knowing that Leonard's group could have tricked Soot into getting the ghosts talking board if he hadn't fallen off the stairs when he did. Paula had restrained from telling him that initially. Apparently her human side also didn't wanted to make her brother feel worse for the actions he had no control over.