For your knowledge the game you are watching have already been played by game engine in those 15 minutes prior your "live" watch time. So there is actually no possibilty of watching the game happen live.
Call it whatever you call it, data is sent periodically to the user.
This data could be added with sound "data".
Obviously there are ways to add sound files to different events, but I think it's a lot more work than you presume
The SW that calculate the score just needs to add, at each change, the information needed for the sound that reflects it.
Stop speculating/estimating how easy things are, if you actually have no experience in that field.
I believe we both speculate and estimate, and (as I said) I think neither of us know what can and cannot the developers do, and what is their priority.