Actually, it appears that it was the third attempt that finally got through, apparently after ringing for some time. That would be frustrating and likely to elicit an under the breath curse... which it did... that happened to get heard by the answering officer.
I’m sure that’s why she was upset. On the other hand, (and I don’t know how long she let it ring, I don’t think it said, but when you are in a panic any time at all seems like a lifetime) it may not have rung very many times and if she called 3 times in succession, (which I think they would know on the other end—perhaps I’m wrong?) and then the first thing the guy heard from her mouth was foul language, I can see where his initial reaction may have been that it was a prank call.
That’s all I’m saying. That may have been why he initially started out handling the call badly.