In a nutshell:
Trial court said “case dismissed” with a summary judgment in favor of CGC and Heritage.
Upon IGB’s appeal, the Superior court said “case undismissed, no liability determined at this time”.
CGC and Heritage appealed to the Supreme Court to try for a re-dismissal, but it looks like the Supreme Court didn’t even take up the appeal and it was simply denied.
So at the present time, basically all parties are back at square one in the trial court. It seems likely they will have to argue this out in a full trial.