Check your BPS Security Log file and post any log entries that are directly related to Jetpack publicize.
BPS Pro Troubleshooting Resources/Links
How to check your website with a Proxy to detect if BPS Pro is blocking something that needs to be whitelisted. How to troubleshoot Security Log Alerts & Errors. How to use the cURL Scanning tools. How to add Plugin Firewall whitelist rules to the Plugin Firewall Whitelist Text Area.
http://forum.ait-pro.com/video-tutorials/#security-log-firewall
BPS Pro General Troubleshooting Steps
http://forum.ait-pro.com/forums/topic/read-me-first-pro/#bps-pro-general-troubleshooting