To have Barcus and the other Deep Gnomes during the Tiefling celebration party, you have to rescue them before dealing with the Goblins.
Source: N4G PC You Can Have Barcus at the Tiefling Party in Baldurs Gate 3 By Following These Steps
To have Barcus and the other Deep Gnomes during the Tiefling celebration party, you have to rescue them before dealing with the Goblins.
Source: N4G PC You Can Have Barcus at the Tiefling Party in Baldurs Gate 3 By Following These Steps