As someone who has previously worked for one of the two ball tracking companies, I can answer this. The system doesn’t know what the bowler has attempted to do, nor does it need to. It’s purely works on the data it’s got post bounce to work out the path the ball is travelling along until impact and then using that information it predicts where the ball would have impacted the stumps, had it not been stopped.Umpires call is in there to help cover the umpires and back there decision making rather than to purely cover for the ball tracking.
That’s interesting, apologies if others have discussed on here but if it works from after the ball has bounced, how does it work out how high or how steep the ball will end up?