@Jacob Burke
The best workaround is to source the value to a custom field, and then reference the custom field in your template.
This is fine when it’s a couple of fields here and there, but it can get nasty if there are a bunch of elements you need to display that aren’t in the native object model.
In those cases, I will typically write all of the content to a custom field on SAVE, and then use the PDF template to display the HTML.
If you only need that logo url, then you can probably use dynamic sourcing so it will work for legacy print jobs as well.