As you have exhibited a skill for reading selectively that will doubtless qualify you to host a radio talk show someday.

First: Why? Don't all the stupid readers flip to the back page and read how it ends?

That's only high school readers of required fiction. Now that we know your reading strategy for Crime and Punishment, let's discuss news.

It's a rule of thumb, learned by people who study journalistic techniques, that most of your readers will not read past the first three paragraphs of a news article unless they are captivated, have nothing else to do, or are obsessive and will read the whole newspaper, even the ads. This explains why the front page, and the back page, are so important, and why so many articles start in either place and are continued inside. Inside is dead space, unless you get 'em in the first three paragraphs.

Anyone who wants to display the still-uncorroborated nature of their sources can do so with a prepositional phrase in the first or second paragraph. Anyone who wants to be able to say they said it with minimized chance of most of his readers seeing it will bury it at the end of page 2.

Second: It was part of the conclusion, conclusions go at the end of the thingy.

Corroboration goes to credibility. It's not "the conclusion". It needs to be up front. You have to put the hay where the horses can see it.

Third: By putting at the end, it is saying despite all which said in the article, it is indicating that the author has not "got enough", and more work needs to be done. If instead the author had put near beginning the reader might get the false impression, that what follows is fullfilling what is needed.

No. He could have put a notice of lack of corroboration in a phrase at the beginning, and still had his disclaimer (which is what it is) at the end.

He knew what he was doing. So do I.