Both .idd and .inx files come from InDesign, so if any kind of idd to inx conversion is doable, it would be done with InDesign and no other. Perhaps it is some kind of export between older versions of the document format, in which case you might need a particular version of InDesign.
In any case, if you have issues with import/export of older InDesign files, it would be best to consult Adobe support.
Updated: January 25, 2023