UE4-MCC LowLevelFatalError Crash On Startup

[Not_The_NSA]

When starting the game, regardless of startup conditions (anticheat enabled/disabled, compatibility settings enabled/disabled for Win7/8, etc), I get about 1/4 second of the intro cutscene audio before the sound cuts out and the window freezes on a black screen. About two minutes later, I get the following error message in a popup window:

LowLevelFatalError [File:Unknown] [Line:1144]
GameThread timed out waiting for RenderThread after 120.00 secs

After clicking OK, the game window closes, but Steam is locked up thinking MCC is still in the play state, and this does not resolve until a reboot.

I have never had this issue before on any other game for this machine, and I've never had this issue before on any other machine for Halo MCC.

I've tried changing/adding/removing compatibility settings on the .exe, forcing the game to launch in windowed mode, pulling a DirectX diagnostics dump (all good AFAIK), uninstalling/reinstalling MCC, uninstalling/reinstalling Steam, uninstalling/reinstalling & rolling back AMD graphics drivers, and uninstalling/reinstalling Windows. Nothing I've tried seems to work. Anybody got any idea what the heck is going on?

Specs -
OS: Windows 11 (23H2, up-to-date)
CPU: Intel i5-13500 (2.50GHz)
GPU: AMD Radeon RX 6700XT (12GB, driver rev. 24.4.1)
RAM: 2x 8GB OLOy DDR4 (16GB, 4800MHz)
Storage: WD-BLACK SN770 SSD (2TB)