Unreal and UWP/COM developers are perfectly fine with writing C++ code with a GC around.
COM and other refcounted ones get a pass. But I'm surprised that Unreal gets away with a mark-and-sweep GC. Perhaps because it's only required for UObjects, and the rest of the codebase can still easily avoid using the GC? You can even cause use-after-free bugs on UObjects, if you want to.
https://atlas.cern/discover/detector/trigger-daq
You can also try to broaden yours.
https://www.ptc.com/en/products/developer-tools/perc
Will this work for you? I guess most likely not, and you really cannot afford any kind of delay, where even a C++ virtual call would be considered a bug, given the 1ms delay.
The point being that only a very tiny population has such requirements, just like barely anyone writes applications 100% fully in Assembly.