Meaning: Finally, on top of that. Used to describe when something bad becomes worse.
In #5437,始末 means "from the beginning to the end" whereas in all other examples, 始末 is used to mean "situation" or "circumstances."
#5437 is copied exactly as I found it. I'm not quite sure about it because it is not at the end of the sentence as all the other examples are. 結末 and probably even 結果 sound like they would be good in context.
#5437 Do you mean 結末 ketsumatus instead of 始末?
I think this is similar to "〜してしまった" or "〜ということになっちゃった". In my grammar book, there is no kanji but if you do a google search, 始末だ comes up often. I'm not very confident about example #5437...