I can bet that is because of the bfa namespace in the xml structure... bfa is a namespace reserved to B1i.. thy not to you namespaces in the creation of the xml structure, thy this:
<Result>
<row>
<col></col>
</row>
<row>
<col></col>
</row>
</Result>
then :
/*[count(/vpf:Msg/vpf:Body/vpf:Payload[./@id='atom15']/*[local-name()='Result']/row)>0]