Brook landed inside a magic summoning circle

• brook was also sommoned in a similar pentagramm in chapter 524
• but he was teleported there by Kuma
• the people who made the circle wanted to summon "Satan" to support them against the long arm tribe

I think many jump to conclusions too fast when they say Ennies Lobby hole was formed the same like the Lulucia hole. Why is there still rocky bridge of the Judicial island remaining above spanning the hole?