It looks like the Discord #developer-ios channel is discontinued as of around Jan 23, 2019. A banner above the discussion thread said, “Support moving to https://community.brave.com. Join us there!”.
In Contributing > Developers > IOS x2 there are only a few topics, none new. And here in Contributing > Developers there appear to be no newer topics than about the same time period: Jan 22.
Where does an iOS developer go for discussion about problems, priorities, and making code contributions?