It seems you've got one less merchant to buy from, Leagle. Bernard won't return to neutral, and charms won't help either. If you're lucky Jaheira may talk to him and maybe (probably not) he'll return to normal. Otherwise, I know of a place where you can lower your reputation if it's getting a bit too high
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The last arrow of Legolas kindled in the air as it flew,
and plunged burning into the heart of a great wolf-chieftain.
All the others fled. -J.R.R. Tolkien, The Lord of the Rings