I see that this thread has been opened for Sitefinity 4.0, but the link you have provided is for a website using Sitefinity 3.7. Can you, please clarify for which version do you want to implement this functionality? If it's for 3.7 I have followed the steps you described and all 3 newsview widgets display fine when set to show news belonging to different categories. What you might want to check is if you have filled in the summary field for each news item, as this is the text that's being displayed in list mode. Also, please make sure you have specified the widget to display the news summary(please refer to the attached screenshot).
If you were referring to Sitefinity 4.x, than check if you are applying the same template for all News widgets for List settings.
I hope you find the above information useful. If you need any further assistance, please write back.
the Telerik team
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