Help me get the camp celebration

I’m going to preface this by saying this is my first ever play through, so I know I did things out of order. I just want to know if the situation can be salvaged.

I talked to the folks in the Grove, heard about the conflicts going on, and eventually made my way to the Goblin Camp. I killed the priestess, but I had a hard time killing the others so I put it off for later. I then freed Halsin, but I didn’t really join forces with him- just wished him luck. I also said I’d help Minthara (I planned to deceive her). Then I eventually made my way back to the Grove and killed the archdruid, which made the druids kill almost all of the tieflings. My journal now says that all these quests are completed- the surviving tieflings escaped but will probably be killed by goblins.

I was just jumping around and exploring the game, so I did not expect or want this outcome. Can I still go back and kill the other two goblin camp leaders, or is that all done? And can I still access the camp celebration, or did I fail too miserably?