This is the  most F of faqs,

<xsl:template match="//PersonName">

which matches the same things as

<xsl:template match="PersonName">

a leading // never does anything useful in a match pattern, it only
changes the default priority.

matches PersonName in no-namespace.

similarly

		<xsl:value-of select="normalize-space(FamilyName)"/>

selects FamilyName in no-namespace

<Enrollment xmlns="http://ns.hr-xml.org/2004-08-02"

sets the default namespace to http://ns.hr-xml.org/2004-08-02
and I would guess that your PersonName and 
FamilyName elements are in that namespace, so these are not matched by
the Xpath expressions above.

add

xmlns:h="http://ns.hr-xml.org/2004-08-02"

to your xsl:stylesheet and then use

<xsl:template match="h:PersonName">
		<xsl:value-of select="normalize-space(h:FamilyName)"/>
		<xsl:text>,</xsl:text>
		<xsl:value-of select="normalize-space(h:GivenName)"/>
		<xsl:text>,</xsl:text>
		<xsl:value-of select="normalize-space(h:MiddleName)"/>
		<xsl:text>,</xsl:text>
		<xsl:value-of select="normalize-space(h:Affix)"/>
		<xsl:text>,</xsl:text>
	</xsl:template>


David