UPDATE = WORKAROUND:
Use the option “Reimport With New File” found if you right click the Data Table in the appropriate Content Folder. This will guarantee that the same Struct applies. This lets me drive the BP from a variety of input data files (all adhering to the Data Table’s Struct contract). Ugly but gets me going. Arguably, the Data Table event graph nodes should have been designed to be driven by Structs, allowing a general purpose BP to support any Data Table that is based on the specified Struct. To my mind, a Data Table’s Struct is effectively its type. Of course, I am as fallible as the next guy; and am happy to be corrected by someone more knowledgeable.