Ok. I tried your suggestion and it works ok. The Growl notification says "This is a sample notification". So that's good.
In my Applescript, the last line before the end is:
display dialog theResult buttons {"Done"} default button 1
end alfred_script
This displays "theResult", which is just a filename as a string, in a button so I can see the filename on my screen.
So, if I add the {query} placeholder in the Notification object and run my script in Alfred, I get a Chinese character output. If I then comment out the line that displays the button with "theResult" then the output appears in English.
So, for now since all I wanted was to display the Growl notification instead of the button dialog, I'm ok. Although it bothers me that I can not understand why adding a button causes Chinese output to Growl.
Thank you for suggesting the simplification since that led to at least an acceptable solution.
I wish I could attach a screenshot but I still can't see how in this edit tool.