UPDATE: I've fixed the issue. It was a problem with ScriptHookVDotNet. Removing it fixed this.
GTA5 closes itself (it doesn't crash, it just closes: no crash report, etc - see here) when I run LoadPlugin EUPMenu.dll in the RPH console. I've tried reinstalling EUPMenu, renaming mods to _mods, adding an exception in Windows Defender for the GTA5 folder, etc, all to no avail.
I've got ReShade+ENB installed so I can't launch RPH directly, but have to launch GTA5 first via Steam then RPH, maybe that could be the issue? No idea. It worked yesterday, but now I've restarted my PC (haven't made any changes to my RPH between the time it worked and now) and it's stopped working. When I launched RPH with the -nodx flag, it crashed on startup, but gave me a crash report this time (attached). Not sure what to try anymore, any advice?
PC specs:
GPU: NVIDIA Quadro P5000
CPU: Intel(R) Xeon(R) CPU E5-2678 v3 @ 2.50GHz
Memory: 12 GB RAM
RPH-crash-report_-nodx.txt