You have two choices to rescue Imoen. One is to go with Galen Bayle(sp) and the other is to go to the graveyard district and.......I won't spoil you.......just know that it isn't a 'rob them blind in the dark' thing, it is an alternative to choosing Galen Bayle. Either way, you end up at the same point, gamewise!
As for the bard thing, I really don't know, other than you may have been taken to the Five Flagon's Inn in the Bridges District (I think this is the bard stronghold).
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Never try to teach a pig to sing; it wastes your time and it annoys the pig