I don't have the R5II, but I have used several similar cameras, and I have spent years in tech product development, so maybe I can give you some general hints.
First up, you say "Everything seems to work OK". This is good!
The firmware is generally a monolithic block of software. You can't realistically be running bits of one version and bits of another version. So, if the camera is working, you're either still on the old version, or you're on the new version. (This does rather depend on how Canon actually manage updates internally, which I don't know because I don't work for Canon, but it should be a safe bet.)
So, go into your camera's menus, find the "firmware" section (the "wrench" section, last tab), and look at the firmware version you are currently running.
- If it's the old version, then you need to try the update again. (Don't turn it off this time!).
- If it's the new version - I think that would be 1.1.1 as of now - then it's fine, the update completed, you're done. IOW don't go looking for problems if it's all working.
I don't know if you can re-apply the update if you're currently running the same version - I don't think you can, and in any case it can't really help anything.
Hope this helps.
