I bet you in a month we'll see a mod that completely addresses this issue and we will all be left wondering why Larian didn't fix it during the entirety of this game's development. I can't believe it would be that hard to just make it so only the character on top of the party list can interact and the others are just treated as NPCs and don't initiate cutscenes/dialogue (or if they do, just swap their positions with the player character, I will take abrupt body swaps over save scumming to get the right character to initiate dialogue any day) yet here we are at almost release with this still being an issue.