Well, no way for any of us to know, and it can’t be confirmed without a direct quote from the Sheriff or one of his staff, but it sure seems like it was Denise from the vantage point we have now. (My opinion).
I also think about how with new information, which should not be taken lightly, opinions can change. But that’s where I am leaning right now. Denise made the call.
Think, this was likely a fast moving crime scene. I have read from victims of crimes, the crime seems to go in slow motion when remembering.
In the fast sequence, whoever made the 911 call acted so quickly, and was very brave. I lean toward Denise, but there is no way to know based on the evidence, even after the release of new information recently.