warum funktioniert dieses xslt script nur im Internet Explorer abere nicht in chrome oder edge?

Hallo,

ich habe ein XSLT Script das eine xml zu einer Tabelle umformen soll. Das Script funktioniert nur in IE11 aber nicht in den anderen Browsern.

...

$index_file="index_station.php";

...

echo '<?xml version="1.0" encoding="ISO-8859-1"?>';
echo '<xsl:stylesheet xmlns="http://www.w3.org/1999/xhtml" >';
?>
<xsl:stylesheet version="1.0"
     xmlns:xsl="http://www.w3.org/1999/XSL/Transform"  
    xmlns:js="http://www.w3.org/1999/xhtml">
<xsl:template match="/">
 

...
      <?php include "index_station_checkbox.php"; ?>
      <hr/>   
      </td></tr>
         <xsl:apply-templates select="KKHABG/PATIENT">
         <xsl:sort select="<?php echo $xmlsort; ?>" />
         </xsl:apply-templates>
        </TABLE> 
     </BODY>
  </HTML>
</xsl:template>

<xsl:template match="PATIENT">
   <tr>
   <td valign="top" class="patientname">
      <xsl:element name="a">
      <xsl:attribute name="href">
      <xsl:value-of select="PatID/@VALUE"/>
      </xsl:attribute>
      <xsl:value-of select="nachname"/>, <xsl:value-of select="vorname"/>
      </xsl:element>
      <br/><xsl:value-of select="alter"/> - Zi./Bett: <xsl:value-of select="FALL/Behand/ort"/></td>
      <td valign="top" widht="100%">
      <table class="befund">
         <xsl:apply-templates select="FALL/Befund" >
         <xsl:sort select="BefZeit" order="descending"/>
         </xsl:apply-templates>   
      </table>
   </td>
   </tr>
   <tr><td colspan="2"><hr/></td></tr>
</xsl:template>

<xsl:template match="FALL/Befund">
<xsl:if test="<?php echo $sourcexml; ?>">
   <tr>
   <td valign="top" width="100px"><xsl:value-of select="Source"/></td>
   <td valign="top" width="40px">
      <div class="tooltip">
      <xsl:element name="a">
      <xsl:attribute name="href">
      <xsl:value-of select="ID/@ZIEL"/>
      <?php echo $var.'&amp;befart='.$befart.'&amp;befundid=';?><xsl:value-of select="ID/@VALUE"/>
      </xsl:attribute>
      <b><xsl:value-of select="ID"/></b>
      </xsl:element>
      <span class="tooltiptext2"><xsl:value-of select="ID/@TOOLTIP"/>      
      </span>
      </div>
   </td>   
   <td valign="top" width="150px"><xsl:value-of select="BefZeit"/></td>
   <td valign="top">
      <div class="tooltip">
      <xsl:choose>
      <xsl:when test="BefArt/@VALUE">
      <xsl:element name="a">
      <xsl:attribute name="href">
      <xsl:value-of select="BefArt/@VALUE"/>
      </xsl:attribute>
      <xsl:attribute name="target" >_blank</xsl:attribute>
      <b><xsl:value-of select="BefArt"/></b>
      </xsl:element>
      </xsl:when>
      <xsl:otherwise>
      <b><xsl:value-of select="BefArt"/></b>   
      </xsl:otherwise>
      </xsl:choose>
      <span class="tooltiptext">
         <!-- <b><xsl:value-of select="BefArt"/></b><br/> /-->
         <xsl:value-of select="BefText" disable-output-escaping="yes"/>
         <br/><br/>
      </span>
      </div>
      </td>
   </tr>
   </xsl:if>
</xsl:template>
</xsl:stylesheet>
HTML, PHP, Webentwicklung, XML