While on the "Connect" accounts tab, I can connect to Youtube, Twitch, and Mixer.
While on the "ReLive" tab, I cannot connect to Youtube or Twitch, but I can connect to Mixer. If I click on YT or Twitch, I get a small loading animation but the button stays off.
750 watt Corsair
z97-Pro with 3503 BIOS
Man I searched for a long time to figure this out. So here it is if anyone ever looks this up. On the ReLive "Live Streaming" tab, you must set up a "Custom Stream". Use the server URL and Connection Key for your Youtube channel and stream a bit to it to verify it's working. After that, you can click on the Youtube button and it will connect. Same with Twitch.
This solution is working on 19.7.2. I took 19.8.1 out because the Pixel Format button is missing in that driver.