[member="Andorreth Vikar"]
If I understood my history lesson correctly, the "No Superweapons or Destruction of Celestial Bodies" rule was largely implemented after the breaking of Corellia. Clearly site staff did not want to redact the finale of a big event that mattered much to all who participated in a site-wide event. Getting uppity about it now will not change what happened.
That being said: There are many writers who enjoy backstories from Corellia and whose stories pertain to Corellia post-breakage. Just because it is not what it was does not mean it cannot be used. One simply has to implement this cataclysmic event and/or try to remedy it IC. There are several other characters who have worked on stabilising and terraforming Brokellia into a habitable place (Mostly the Corellian League).
It is also worth noting that the One Sith left during its' collapse, the Corellian League rebelled and took Corellia back.
OR
Here is a suggestion: There are a hundred other planets, some with much and some with little lore. If your story require a complete planet, why not try to give more lore to one that has little? Help build the greater Star Wars: Chaos universe by claiming an unorthodox home. Do a site search, see what happened, and bring the thunder.