When you make the view template, and remember to put {{!!created}} in the text field, the date should show up in view mode on EVERY tiddler. If it doesn't, then you've probably done something wrong in the creation of the template tiddler. The dates should show up with the default formatting.
Sometimes when you type something into a tag field, you might accidentally add a space. So be sure that the correct tag has been submitted.
Another way to approach it is to put something like this in a tiddler:
<$list filter="[tag[Journal]!sort[created]]">
<$link/> // {{!!created}}// <br/>
</$list>
This will list your journal entries and show the "created" date it's seeing. That way you can pick out any discrepancies.
HTH