On my first playthrough, I had her fixed 2 times in a row during Act 2.

On my second playthrough - after Patch 2 and Hotfix 5, I've recruited Karlach earlier and fixed her 1 time at the grove. But for the second time, Dammon says - "see you in Baldur Gate!". WTF?? I don't have the second piece of the infernal metal, but when I find it, then what, Dammon will refuse to proceed till Act 3??