This just reminded me of another issue I have run across, that must be related to the issue here.

I also would like to print the name of the package that is the parent of an element, but this too prints as blank.

This should be very easy to test on your side.

Add Single Attribute of a related element for an element.

Type: Parent
Direction: Normal

To Element Type: Any

Print name- hyperlinked

I know from scripting in Sparx that Packages have a different shape from other elements, so maybe you need some special handling here for Packages.