I had a quick check and I cannot see any implied rules that would cause your traffic to be blocked.
If you have a hardware appliance with SecureXL on, you could try turning off SecureXL and seeing if you can see anything further within fw monitor. I would recommend just checking your current loading, as if you box is already highly utilized you will want to disable during a maintenance window.
If you don't see anything further with SecureXL disabled, then I would suggest raising a TAC case.
Regards
Mark