Bug - One Last Drink Ending

[Jonasgarland]

In trying to complete this quest, I've come across a bug where I've managed to talk Ruanga into attending the party. However, I don't have the option to poison the captain, only to hand over the drinks which results in the default crew members dying. I do have the poison and discovered the journal, though had done that before ever speaking to Ruanga. My quest journal also reads as though she has refused to attend, which she initially did. I spoke to her again, and managed to convince her to attend. I do have a save going back before I spoke to her, but I've read elsewhere that given I've already picked up the poison (which was when I first visited Thirdborn), it will still be an issue?

[William Jolliff]

I also have this issue. I picked up the poison on accident before hand. I even tried reporting it to the Tira nui. It won't let me switch the drinks. I told her I'd switch the drinks and I very much intend to. 

[ShadowBruno]

I have this same bug, Journal says Ruanga refused; the bartender gives me the drinks and there's one gray option that needs 6 constitution (I don't know what it does) and a "Sure thing" one that doesn't switch anything. When you go upstairs there's only a single option to give drinks to the captain, which kills Ruanga and Kowha, again with no option to do anything different. The order I did things, if it helps: I got the poison and book right after getting the quest, confronted Ngunu about it, showed to the policeman in town (both encounters apparently didn't matter, they just ignored the threat), talked to Ruanga first (she said she wouldnt go but I managed to change her mind later), then Tauwe and lastly Kowha, and came back to the bar. I'm gonna finish this quest now and hope it's fixed for future playthroughs.

[Cross-Section]

Same issue. I started the quest, found the poison while exploring the town, talked to Tauwe, Ruanga (couldn't convince her to come, didn't mention the poison) and Kowha. Got the drinks, saw the poisoning of Kowha, end quest. Was a bit perplexed as to why I couldn't say anything about the poison at the Inn, so I looked up a guide and saw that you can mention it to Ruanga for a different ending. So I reloaded just before going to the Inn for the ending, went to Ruanga, talked about switching the poisons and convinced her to come with a Resolve check. But I didn't get any different dialogue when picking up the drinks nor when talking to the Captain, and poisoning proceeds as normal.

Seems like it's fairly easy to break progression for the switcharoo ending.

[slipstream8]

Same experience as the OP for me. This has not been patched as of March 21 in Version 1.3.0.0.

[Wrongtree]

It seems like all of us tried warning Tira Nui Hajime, I'm wondering if this is what's causing the bug? I still have the poison in my inventory. I found the poison and book long before doing this quest.

[RDRadio]

I have the same bug, and another one where I can't turn in reward missions. Shatterscarp is completely broken...