Change URL host without chaining in the User browser

Sounds like you may want to look at using a stream profile to perform some custom rewriting on the response since the application requires the .local address, as well as changing the

Host

 Example which replaces xyz.local with xyz.com in response content
 Prevents server compression in responses
when HTTP_REQUEST {
    Change the Host header to the internal value 
   HTTP::host "xyz.local"

    Disable the stream until we're ready
   STREAM::disable

    You always need to make sure the response content is uncompressed, so the data can be properly modified
   HTTP::header remove "Accept-Encoding"
}
when HTTP_RESPONSE {
    Typically you may only want to rewrite certain content types (like text or html)
   if {[HTTP::header value Content-Type] contains "text"}{
       Replace the values for xyz.local with xyz.com
      STREAM::expression {@xyz.local@xyz.com@}

       You may consider using this instead for multiple rewrites (or ensuring a url reference
      STREAM::expression {@://xyz.local@://xyz.com@ @://www.xyz.local@://www.xyz.com@ @}

       Enable the stream for this response
      STREAM::enable
   }
} 

Hope this helps.