Definitely, is a firewall/network/configuration issue, please double check firewall rules/certs/network segments.
You can check some of previous answered questions with the same error:
http://answers.splunk.com/answers/218422/tcpoutputproc-cooked-connection-to-iptimed-out.html
http://answers.splunk.com/answers/38206/cooked-connection-timed-out.html
And this about digital certs:
http://wiki.splunk.com/Community:Splunk2Splunk_SSL_DefaultCerts
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