Nobody made a 999 call. The available evidence (including Jean Rowe's) makes it obvious that a log reference to 999 was a mistake by a police officer.
I disagree, there certainly was a '999' call, and the officer who's task it was to monitor it, did make a witness statement but at a meeting between Essex police and the DPP, they decided to not seek to rely on that officers evidence! Now, if that officer wasn't monitoring a 999 call, why wouldn't Essex police and the DPP want him to testify about the call he was monitoring, what he heard, etc, etc, etc...