Answer
Rather than trying to bind a dynamic image field's value directly into the image element, store the logo/image in the Media Item page/table and retrieve it with a SQL query that selects the media_object based on identifying values passed in as bind variables (for example, a description and name lookup keyed by company number and an image-type label like 'COMPANY_LOGO'). Upload the actual image file through the Media Item page's browse functionality first, then reference it this way in the report's image element — this indirection through Media Item is what makes a per-record dynamic logo/image actually render, where binding the image element straight to a data field doesn't.