Wouldn't it have been less effort and simpler to replace the custom code with an existing XML parser? It appears that in your case the simplest thing would have been easy, though the aphorism doesn't promise "easy".
If using a library wasn't possible for you due to NIH-related business requirements and given the wide proliferation of XML libraries under a multitude of licenses, then your pain appears to have been organizationally self-inflicted. That's going to be hard to generalize to others in different organizations.
