Form fields missing entirely or incorrect in PDField list

Running this code on the attached file results in incorrect and missing results:

PDDocument doc = PDDocument.load( new File(filePath) );
PDAcroForm form = doc.getDocumentCatalog().getAcroForm();
List<PDField> fields = form.getFields();
for ( int i=0; i<fields.size(); i++ ) {
System.out.println("Name:" + fields.get.getFullyQualifiedName());
}

The output is:
Name:2
Name:Step 2
Name:Image 2
Name:Button 2
Name:Button 5
Name:Image 5

The file was generated in InDesign and the form fields created there, so they should be recognizable. You can see that the part of the form fields after the dot was removed and the two fields on page 4 are missing entirely.

I tested it using 1.8.8 and a very recent 2.0.0 snapshot, both yielded the same results.