to watch YT Videos you could try the F-Droid Version NewPipe | F-Droid - Free and Open Source Android App Repository
I assume that those apps are dependet on GSF and even if microG is somehow pretending this, there is never a guarantee it works and it can break every time.
Edit for further reference FP4: Google-free Android - #77 by AnotherElk
I woudl also suggest when you find issues with specific apps, to report to Murena, so in case there are bugs in the system causing this, those can be fixed