So, it is not the final url, not technically, but it is the url that is configured as the main site domain, so i dont know why there would be an issue.
I just input http://www.thundertech.com as the source page url and that worked just fine. It is just when we point to a page url of the site we are on that we are having the issue.
So for example: http://test.[example].com/sandbox/interest-dynamic-content
The configured main site domain is: test.[example].com
And the page type for the interest-dynamic-content is Page (menu item) and a portal template i created. Not sure what the issue could be.