There are tons of opportunities to solve convos without a Cha skill.
The convo with Kagha has so many different options other than persuasion to save the kid. Some I've encountered:
Wood elf - Brings up Sylvanus as someone who is intimately familiar with their god.
Paladin - Calls into question her judicial authority and offers to arbitrate instead.
Druid - Brings up some hippie gweneth paltrow scented candles or something.
Hidden religion roll - I think this one only showed up because it rolled in the background (the little 20 in the corner) before the speech options came up. As a wizard, you would probably do well on that roll and have the ability to convince her to stop being a meanie.
Honestly, Insight is by far the most important skill for convos. 90% of your convos with your companions have at least one insight check, and the Cha checks are usually pretty low.
Besides all that, failing rolls is part of DnD. Nothing is a game over (other than your last death save), so enjoy the ride and let the story take you where it will. I will definitely be playing a low Cha Durge at some point and a low Int Pally. Seeing what happens when they fuck up is going to be half the fun.
