Piratecat
Sesquipedalian
Like others, I'm not sure you did anything wrong. Trying to figure out what I might have handled differently...
Encounter 1. Yeah, sometimes players skip awesome plot. I'd make sure this possibly comes back to bite them, but I'd let it go too.
Encounter 2: I'd hide, too, if something that looked just like an attack force came up. If you really want a roleplaying encounter that doesn't have the possibility of becoming hostile, make them obvious non-combatants. Maybe 1-3 dromites on foot, or riding non-combat mounts. In extremity give them a white flag.
If they choose to hide, that's okay. They don't get the information that the dromites had. When they figure out they want or need it, they can seek out the dromites themselves.
Encounter 3: They fail the encounter when they threaten her. She looks at them sadly, shakes her head, and disappears (maybe pointing towards the city, but saying nothing) -- obviously in physical pain due to the cyst corruption. The group says, "Huh. She didn't attack. Maybe we were wrong." And then they learn from that.
I think the important thing here is not to stop the game and tell them she's a good guy. That felt like railroading, maybe? I'm a big believer in giving the players the freedom to make dumb goofs.
Encounter 4: The PCs are going in blind. I'd have them see the ruined city in the distance. They'd probably bite at it, as it's a Clue (tm), so then I'd spring the dragon on 'em!
I wouldn't worry. Sounds like it was just one of those games. The next one will be better.
Encounter 1. Yeah, sometimes players skip awesome plot. I'd make sure this possibly comes back to bite them, but I'd let it go too.
Encounter 2: I'd hide, too, if something that looked just like an attack force came up. If you really want a roleplaying encounter that doesn't have the possibility of becoming hostile, make them obvious non-combatants. Maybe 1-3 dromites on foot, or riding non-combat mounts. In extremity give them a white flag.
If they choose to hide, that's okay. They don't get the information that the dromites had. When they figure out they want or need it, they can seek out the dromites themselves.
Encounter 3: They fail the encounter when they threaten her. She looks at them sadly, shakes her head, and disappears (maybe pointing towards the city, but saying nothing) -- obviously in physical pain due to the cyst corruption. The group says, "Huh. She didn't attack. Maybe we were wrong." And then they learn from that.
I think the important thing here is not to stop the game and tell them she's a good guy. That felt like railroading, maybe? I'm a big believer in giving the players the freedom to make dumb goofs.

Encounter 4: The PCs are going in blind. I'd have them see the ruined city in the distance. They'd probably bite at it, as it's a Clue (tm), so then I'd spring the dragon on 'em!
I wouldn't worry. Sounds like it was just one of those games. The next one will be better.