How does CrashReportHandler.SetUserMetadata work?

I'm trying to understand how Unity Cloud Diagnostics works, and there is not a ton of information available.

I have a bug I can't reproduce on dev, but is happening on the live version according to reports from many users. I'm pretty sure it's caused by an unhandled exception, and I have a rough idea where in the code is. If the stack traces or attached logs were searchable, I could confirm my hypothesis, but unless I'm missing something, they aren't (I tried searching by keyword, but that doesn't seem to work at all)

So what I want to do, is to set a metadata before the suspicious code begins, and remove it after it ends. That way, if an exception occurs there, I can then find it by its metadata.

I just have to make sure that metadada is cleared the next time the game starts, otherwise all other unrelated exceptions will be marked as well. My question is: do keys set using CrashReportHandler.SetUserMetadata last only for the current session? Or are they persisted between sessions?

If there's a better way to do what I want, I welcome any suggestions.

Thanks, Mike