Hey guys, I had the exact same problem, and I tried a few of the solutions listed on this thred to no effect.
After trying to rush it maybe 10 times I decided to try standing completely still while I opened the gate, and while it took a few seconds for them all to become agressive, they all did one by one in the end. So basically try standing still at the gate when you open it and wait for them to turn red.
I read a fix in the comments and it actually worked!!!!!
Once opening the cage door wait for a good amount of the npc’s to come out. I waited till about 15 showed up and was able to complete the story.
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