Chances are they just do not exist since no one has matched them yet. You can download a good selection of known names from the OIV repo and see if that helps.
As far as bullet force is concerned, I played around with that a few months ago and I think each weapon has different force multipliers depending on the entity hit (ped, vehicle etc.) that you can modify in the respective ymt.
If you have little C++ experience and no reverse engineering experience this will be a tough one. I would recommend familiarizing yourself with tools such IDA (or Ghidra), x64dbg and Cheat Engine. Also look into how natives work in RAGE. Then you can follow the native I mentioned above in game code and see where the actual screen effect code is located. Then work from there.
Can you send or attach a full verbose log with all this once the game has loaded in? I do not have the game installed on my current machine, but I can then probably quickly find the entry in the log.
I have never done C++ with VSC, but this should in theory all you need: C++ programming with Visual Studio Code. Compile to dll while including the proper SH headers and libs, rename to asi and you should be good to go.
Only permanent solution for you would be to move RDR onto a somewhat modern/fast disk. No matter the amount of caching and optimizations, if the disk is slow, it will cause problems.
I think those are only attached/shown if the ped is not a mission ped, i.e. you need to set it as no longer needed first. If that is not desirable, maybe if you use SET_PED_CONFIG_FLAG with PCF_GiveAmbientDefaultTaskIfMissionPed it brings back those prompts, but that is a big guess on my end.
I am not sure, but I have never seen this problem (nor does it make much sense) and the Turkish i-problem can lead to many very odd side effects. So would be great to rule that out first.