Your table starts with:
Using xml Syntax Highlighting
<w:tblPr>
<w:tblStyle w:val="ac"/>
<w:tblW w:w="0" w:type="auto"/>
<w:tblLook w:val="04A0" w:firstRow="1" w:lastRow="0" w:firstColumn="1" w:lastColumn="0" w:noHBand="0" w:noVBand="1"/>
</w:tblPr>
Parsed in 0.001 seconds, using
GeSHi 1.0.8.4
Changing a column width has the effect of changing this to:
Using xml Syntax Highlighting
<w:tblPr>
<w:tblStyle w:val="TableGrid"/>
<w:tblW w:w="0" w:type="auto"/>
<w:tblLayout w:type="fixed"/>
<w:tblLook w:val="04A0" w:firstRow="1" w:lastRow="0" w:firstColumn="1" w:lastColumn="0" w:noHBand="0" w:noVBand="1"/>
</w:tblPr>
Parsed in 0.001 seconds, using
GeSHi 1.0.8.4
(and adding that style to styles.xml)
It adds an extra w:gridCol (correcting an issue?), and changes your w:tcW/@w:w="0" values to values appropriate for each cell (based on the grid)
If you make these changes manually or using docx4j, you'll see the missing content.
I guess docx4j creeates better PDF output with this adjusted table?