Actually... it is your WIS that decides on whether you manage to expose the fraud of the Tradesmeet "Dragonslayer".
Potions of Insight beckons.
As for Jed in IWD, it is your class that determines whether or not you get the option to sober him up. The Bard gives you the best outcome, while the Mage gives you a bittersweet one.
Short of repungant CHA, high CHA is only needed in one critical dialogue in SoA. WIS is needed in two. INT is needed in one. As far as I can recall.