Well, I haven’t been able to reproduce 9999 ping here when adding a Shipping Win64 build to Steam and opening on two different systems at two different locations. If you have time, I’d like you to download this small test project:
Run the .exe as you would your game (add it to your Steam library and run on two different systems). Click Host on one system, and once it says “Creation Successful,” click Find on other. Wait a minute or less and ping should appear on Client. Let me know if it doesn’t.
Without being able to see what’s causing ping miscalculation in your project, and with no logs to look at, there isn’t much more I can do. only other thing I can ask you to try is to build game as a Development build and try same thing, then get those logs. I think reason you’re not finding logs is because it’s a shipping build.
I have seen this issue pop up for a few people on AnswerHub, so I’d like to nail it down. If I can figure it out somewhere else, I’ll post here and let you know.