Reverse Proxy for external address (URL)

OK, but it is possible make this configuration? This "external to external" reverse proxy?

We don´t have administration on remote server, in fact, is a URL that anyone can access. So in theory, it´s just rewrite the host and send it to the POOL that have as member, the valid IP of the remote server.

I just need a evidence that it is possible or not. Better than that, if someone could show me a case would be perfect!

thanks in advance!