In the Inventor forum I was told by Mr. Shiue, "when you reference a file in an iLogic rule, Inventor does not establish a link between the Inventor file and the reference file (Excel xls). It is because a rule can be an external rule. There is no efficient way Inventor captures that. Pack&Go only looks for related files that prevents Inventor from opening a given file."
It would be nice if Inventor included an option to also search for and include .xls files referenced in the iLogic code. Especially if the file is saved in the projects "workspace" folder.
Below is the link to the original Inventor forum post for more details:
https://forums.autodesk.com/t5/inventor-forum/referenced-excel-xls-files-not-included-in-pack-and-go...
Thanks!