I haven't paid attention to the flags for these in a hot minute so take my words with a grain of salt, but IIRC, the reason this issue happens is that it doesn't properly categorise the event as a break-up, but as a "secret third thing" that's still described as not being together in the flag description. I assume it was this way because they thought they might have to do content related to it in the future since it's a bit more specific, but then they... kind of didn't, leading to having to work with the more default paths. The "Illithid Alliance" flag is never used again in other files. It's only present in the Elfsong Tavern scene. It's the same for the "Stayed as friends" Spawn flag. Also never brought up in another file.
What's confusing about the AA branch though, is that I have seen videos where the player has clearly chosen to break up with him, no alliance no nothing (unless you can choose to do the alliance but also go with the Emperor?) when in this instance the breakup is actually properly flagged. But it still triggers lines it's not supposed to, if the videos on it are any indication...? I'm a bit confused over why that is. Maybe someone squided-out then went with Karlach...? There is another flag that's now properly working in-game, that is intended for Tav's that left for Avernus or the Astral plane- and it seems to now trigger for Mindflayers as well? I'm trying to piece the whole thing together, since that flag isn't anywhere else except in the epilogue file. That flag is meant for characters who have been torn apart, not have actively broken up. So it's strange. To me it's very obviously broken, especially with some of the devnotes available that contradict a lot of this.
With Spawn, they have now made the branch available for (formerly) romanced Mindflayer Tav- they're not in a relationship, and despite what you chose in the epilogue, they seem to have stayed away for those 6 months. HOWEVER, there are options for a (currently) romanced Tav where you can say things to him as a Full Ceremorph, which would be impossible to trigger as is. I'm not sure if it was force of habit at play there, since in the Epilogue they just add Ceremorph options for almost every dialogue line.
