There's no way Spencer wouldn't have fallen off the building when Harmoo attacked him on the ledge.
Stewart and Oliver can get arrested for breaking and entering and vandalizing the iCarly studio and arrested for assault for making their cat attack Spencer.
The cops can get sued and fired for refusing to arrest Stewart and Oliver and the ticket that the cop wrote to Carly and Sam is invalid because the car in the studio is a prop.
When Mrs. Benson goes to Freddie's apartment and find him gone. She tries to call the police to report him missing and she tells the cops that he's 15 years old. Even though the cops say that Freddie is an adult. He's still a minor. Minors under 18 or 17 in some states can be considered missing children.
When everyone races down to Freddie's room to rescue the cat on the ledge, Spencer climbs out the window to bring the cat back in. When the camera pans down, it is clear there is multiple floors above ground level, yet Freddie's room has the elevator shaft starting there, meaning he is on the bottom floor. Looking down, Freddie should either be at or just above ground level, not multiple floors above ground level.
Spencer throws the cat out of the window on the eight floor. Yet it lands in Freddie's apartment, which is above the eight floor. Meaning the cat fell up.