I picked up most of the things you described. It was very detailed and the flow helped me dive into the narrative.
Certainly, it seems absurd the old lady wouldn't do anything about it. But life can be absurd sometimes. And beyond that,. I think the interesting part wasn't if it was believable or not, but rather what the reader feels when being witness to a death no one cares about in the story. As human nature, we want to save the woman, and wouldn't believe that anybody else wouldn't, especially your own family.. In this respect is when I believe the story doesn't seem real, but I think it's because we are reluctant to see that sort of thing happening, not because of the writer's development of events.
Anyway, I guess we as writers always get the feeling that we are missing something when we finish our stories. I don't know about experienced writers, but it happens to me hehe.