Issues with routing to external endpoint

Hi, 

I am trying to route all the request to an external endpoint (outside our organization) but getting the below exception.

On a side note, I get a successful response when posting the request to that endpoint via soapUI. 

URL - https://www.gateway.uat.asic.gov.au:443/gateway/ExternalBnSearchPort

Response:

<env:Envelope xmlns:env="http://www.w3.org/2003/05/soap-envelope">
<env:Body>
<env:Fault>
<env:Code>
<env:Value>env:Receiver</env:Value>
</env:Code>
<env:Reason>
<env:Text xml:lang="en-US">Internal Error (from server)</env:Text>
</env:Reason>
</env:Fault>
</env:Body>
</env:Envelope>

to give you more insight I am also attaching the HTTP logs from the tool for request routed and direct to the endpoint

- direct via soapUI  

- routed via mock

Route_Issue.JPG shows the transaction log snapshot, that the request is routed out to the endpoint.