I have already repaired and even deleted the minecraft folder Twitch app creates. I used ATLauncher to load a curse modpack and It booted on their launcher perfectly fine. Im so confused right now.
I think I got the same issue and still trying to find a fix. Ill post back If I fine a fix.
This is whats in my Log (Failed to find Minecraft resource version 1.15.2-20200307.202953 at E:\Program Files (x86)\Minecraft\Curse\Minecraft\Install\libraries\net\minecraftforge\forge\1.15.2-31.1.30\forge-1.15.2-31.1.30-client.jar)