failed a perception check probably

Gale: I don't think this is strictly legal.

Wyll: It's not stealing, it's acquiring.

Astarion: Shhhhh.

Gale: Surely there's a spell for this sort of thing.

Astarion: Quiet.

Gale: [exasperated sigh]

[Locking opening SFX]

Astarion: A little souvenir.

Gale: Wealth is to be shared, I suppose.

you could meet Minsc in Act 1 and optionally romance him at the tiefling/goblin party. they didn't get very far with this it seems, and there's no dialogue or animation, just flags and placeholder descriptions.

an unused flag in the files indicates that prisoners are used as healing sources for the restoration pods in the illithid colony and ships.

Alfira has a dialogue trigger that gives her +1 Approval in at least one Act 3 scene, indicating she could be recruited and stay in the party until then.

there was an encounter with a sea hag in Act 3, and an unused "Pendulum of Malagard" legendary amulet.

Thieves' Cant was an available passive.

cut instruments include the shawm, saxophone, dulcimer, and bagpipes.

cut weapons include slings, darts, and wands.

cut spells include magic jar, comprehend languages, dispel magic, true seeing, levitate, and more.

Shadowheart's mother was named Eliriana (a female elf), and her father was named Sebastian (a male human).

here's this early Astarion model (sorry):

and an early Shadowheart: