Cora is one of the murder targets during the quest Investigate the Murders. "Master Meztli" is actually the Bhaalist aspirant Dolor, who seeks to kill her and chop off her hand to gain the approval of the Murder Tribunal and become an Assassin of Bhaal.
Upon approaching Cora, she tells the party that she's about to taste some of "Master Meztli's" wine. A successful passive medicine check reveals that the wine smells sickly sweet, with an acrid note on the periphery, indicating poison. The party will face several dialogue options:
- Cora Highberry, your life is in danger. A serial killer is after you.
- I would love a glass, Master Meztli.
- I'm afraid I must decline, but I hope you enjoy your wine.
- I think it's only polite that we let Master Meztli drink first, or should I say... Dolor?
- Attack the poisoner.
Choosing "I would love a glass" or "I hope you enjoy your wine" results in Cora being poisoned and killed. Otherwise, "Master Meztli" reveals himself to be the serial killer Dolor and is infuriated that his perfect crime was interrupted. He summons four doppelgangers to keep the party busy and uses a (scripted variation of) boots with Dimension Door at level 5 that teleports 100 meters (66~ feet) away. One of the corpses contains a Tombstone Shop Key necessary for later on in the quest. Successfully warning Cora Highberry earns the 
Inspirational Event Wine Connoisseur (Noble background).
The party can also attempt to kill her themselves in order to complete Impress the Murder Tribunal.
After the doppelgangers have been defeated, Cora can be found inside her home along with her husband and two orphans whom the pair are looking after. She thanks the party profusely for saving her life and rewards them with gold.
Act 3 Spoilers! This section reveals details about the story of Baldur's Gate 3.