Microsoft released an automated troubleshooting tool for Office 365 hybrid deployment :
This tool will help you verify your Hybrid configuration once the wizard end, or can help you if you have any issues with your configuration.
The tool can export all the results in an XML file that you can forward to Microsoft Support.
Note : The tool only works with Internet Explorer, and need to be run on the server where you executed the HCW. It also need an internet connectivity.