Here’s something to consider along these lines. We are assuming that the phone call two weeks ago was valid. I have seen women claim their significant other wanted to kill them, when what they actually wanted was him out of the house. They were angry. They wanted to manipulate the courts, regarding custody. It’s a real mess, and I’m certain you’ve seen it too.
She may have in fact had some abrasions that made it look like he was being unreasonably rough with her. The fact is though, she may have been clobbering him, and he may have merely held her wrists so as not to receive more punches.
The admission of a recording from two weeks ago presupposes her version of the story was the gospel truth, when it may not have been at all.
For that reason, I do feel an obligation to offer up a devil’s advocate defense of the ‘supposed’ person who wanted her dead two weeks ago. The fact is, that claim may have been the furthest thing from the truth. And admitting this evidence could very easily influence a jury to jump to false conclusions.
You can put together a number of not so solid bits of evidence, that will look pretty impressive by the time they are all presented, this being one of them. They may in fact represent a complete railroading of the suspect too.
By the way, thinking more about yesterday's question, I think part of the question depends on whether the 911 call is considered "testimonial" evidence. Otherwise, I think it might get in regardless of whether it is hearsay or not. Seems like it could be either an excited utterance or a present sense impression.