[DNSB]

One item is how did you generate a toc.ncx with every src changed to scr for all the pagelist entries?

Then there are the two pairs of entries pointing to the same target. Again, this is not valid.

  <navPoint id="navPoint1" playOrder="1">
    <navLabel><text>Báj</text></navLabel>
    <content src="Text/cover.xhtml"/>
  
    <navPoint id="navPoint2" playOrder="2">
      <navLabel><text>obálka</text></navLabel>
      <content src="Text/cover.xhtml"/>
    </navPoint>

  <navPoint id="navPoint33" playOrder="33">
    <navLabel><text>Báj</text></navLabel>
    <content src="Text/afterword.xhtml"/>
  
    <navPoint id="navPoint34" playOrder="34">
      <navLabel><text>doslov (Jaroslav Putík)</text></navLabel>
      <content src="Text/afterword.xhtml"/>
    </navPoint>

I would suggesting correcting these errors and then testing the epub again.