akka-camel jetty producer: getting exception which I am not able to catch

Use case: I have a REST endpoint which is developed with Spray Routing. It
receives requests from clients and for some services it calls another REST
service which is hosted on another server. After receiving response from
remote REST service it does some processing and returns the result back to
the client.

Implementation: can be found at
https://github.com/rajvaibhav/akka-camel-producer-example.git

I am getting "Internal server error" after calling
http://localhost:8080/ping. I am not able to trace the Exception or the
cause. Probably I am not able to configure akka-camel properly. The
application is running properly if I remove the askakka-camel Producer code
from the application.

Please help me find the issue. I also need help in how to log any uncaught
exception in an actor.

Any help appreciated!