It appears ABC 7 is the new insider when it comes to the Ray McDonald case. On Friday, they reported that McDonald called a San Jose police officer either before or around the time of the 911 call, and this officer was a part-time employee of the 49ers. A day later, ABC 7 has a few more details. It is worth noting however that these new details create more questions than answers. They don't tell us any more about whether or not Ray McDonald battered his fiancee on August 30/31.
ABC 7 had some audio from a 911 call, but they do not say if that is the entire audio, or just a portion of it. The audio says, "There's a new RP saying that her fiancee was hitting her. They're at this address." RP stands for "reporting party", which indicates there was a separate 911 call. They do not have any audio for that, so we are left in the dark on this.
The ABC 7 article mentions that lawyers told them 911 calls are typically considered hearsay. Other currently practicing lawyers can weigh in, but as I understand it, while a 911 call is hearsay, it can often be admitted under one of the exceptions. This includes things like excited utterances and present sense impression. Hearsay in general is not admitted because there are questions of the reliable nature of it. However, there are exceptions to the hearsay rule. With an excited utterance or a present sense impression, there is the idea that they are less likely to be lying because of the context in which they made the statements. Currently practicing lawyers can go into more detail on what is one of the more confusing things from law school (just behind various aspects of property law!).
For now, this 911 call is simply one more fact in this case. The District Attorney's office has received the case from the police and is in the midst of determining whether or not to press charges, or request further investigation. There is no timeline on when they will announce whether or not charges will be filed.