In order to go to panel rooms 7-13 and Main Events, you must go to the convention center. The Greater Columbus Convention Center (GCCC) is connected to the Hyatt by a bridge.
Get to this bridge by going to the 2nd floor of the Hyatt and heading towards the hallway between Union and Franklin. Pass these rooms and continue to the long hallway that leads to the escalators down to the GCCC.
Main Events and Panel 7 is immediately on your left and Panels 8-13 (B-pod) are a little further down on the left and on the second floor.