I just had the same bug thas was described and archived here:
https://forum-en.gw2archive.eu/forum/archive/story/BUG-The-Battle-of-Fort-Trinity/first
I did the previous mission in multiplayer with another character and then we tried to do Battle for Fort Trinity together as well. I was launching all previous missions, so I launched this one as well and we couldn’t go past “Report to Traherarne….” point right at the beginning. Everything was as described in the linked thread – Trahearne’s dialogue with 2 NPCs ended, the star above his head disappeared and nothing happened.
After 2 attempts at this I figured out the other player should launch the mission and when we did this, we were able to finally proceed.
Since there were questions about this in the other thread: when talking with the Pale Tree we both chose the same fear – option number 1 – the fear of injuring someone close (we were playing in multiplayer as well and I chose the option).
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