My best guess.
I would create a new field in the table I want to display.
I would put this field beside a portal showing the url from the related table.
The when I go into each record I simply copy and paste the url from the related table into my displayed table.
Then underneath there would be a webviewer that now shows the url that has just been copy and pasted into my displayed table.
This is my best workaround.
To refine that idea, the portal rows could be turned into buttons such that clicking the button performs a set field to set the URL field specified for the web viewer to the value of the URL text in the clicked portal row.
Thanks Phil! I need to learn more about buttons :)