I am poking around, installing as many of those as I can find in my dev environment, and nothing has hit yet. I can’t find the following plugins:
Google Author (I found and installed “Google Author Link” but I don’t know if it’s the same one that you have installed)
Meta
titan creator
wordpress help
wp cone
Have you tried deactivating all of those plugins to see if it works?
I’d love to get to the bottom of this, but without admin access to the back end of your site, I am not sure what else I can do.
The way my plugin works is by evaluating the date of the post (which is determined within what is called the WordPress “Loop”) and if the difference between today and the date is greater than the number you set in the settings, it places a link to an additional CSS stylesheet in the code on the page, which hides the date.
In looking at your site, that link/stylesheet is not being placed into older posts.
If I were you, I’d begin by changing the days to 3, or 4, or 20 (try several) in the settings of my plugin, to see if it works.
If that doesn’t work, it means that something within your WordPress installation—and I still suspect a plugin, though it might be the theme itself—is either (a) changing the date being output from within the Loop, or (b) changing today’s date being reported to the server.
If you are willing to grant access to your site to a stranger, I’m willing to hop in the back end and see if I can track down the culprit. Don’t post the username and password here, but feel free to email me credentials, and I’ll have a look.
In the meantime, I am releasing a patch (based on an inefficiency I found thanks to combing through the plugin for your sake!) that has an outside chance of working for you, so later today once you see version 2.1 of my plugin, you can try that.
I do hope we can get this resolved!