I mean, it takes around 20-30 minutes to reproduce, but yes - I have a 100% repro rate and relative stability for just about everything else. That’s why I’m hoping I can be helpful / can get help. 
I’ve changed my journald settings, we’ll see if my next crash tells us more.
No CPU overclocking outside of default turboing behavior. RAM is technically overclocked, but I’m just using the XMP/DOCP profile. Even then, I was actually running on stock DDR4 speeds when I updated by BIOS since I forgot to re-enable XMP, so that means I’ve accidentally tested that as well (and was still able to repro).
I’m not using the LTS kernel, but I suppose I could give it a shot to see if I can still reproduce. It’ll at least tell me if this is a kernel-level change. I’ll test it out tomorrow since I don’t want to sit around for the 20-30 minutes while it encodes this late at night.