I’m confused by why they would do this, and at the same time, why not for private text messages.
I’m in favor of encrypting as much communication as possible, but I don’t think many of Discord’s users were complaining that their voice chart wasn’t secure. I’d expect more of them to care about text chart, which is less effort to spy on.
There was a recent related discussion on Hacker News and the top comment discusses why this sort of solution is not likely to be the best fit for smaller organizations. In short, doing it well requires time and effort from someone technically sophisticated, who must do more than the bare minimum for good results, as you just learned.
Even then, it’s likely to be less reliable than solutions hosted by big corporations and when there’s a problem, it’s your problem. I don’t want to discourage you, but understand what you’re committing to and make sure you have adequate buy-in in your organization.