I have a 7706 running 7.3 with SUP2E and F348XP-23 cards. I am seeing different information on whether or not multiple destinations per monitor session are allowed. I did find this:
Prior to Cisco NX-OS Release 7.2(0)D1(1), multiple SPAN destinations are not supported when an F Series module is present in a VDC. If multiple SPAN destinations are configured in a SPAN session, the session is disabled until the F Series module is powered down or moved to another VDC or the multiple SPAN destinations are reduced to a single destination.
from
https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus7000/sw/system-management/guide/b_Cisco_Nexus_7000_Series_NX-OS_System_Management_Configuration_Guide/b_Cisco_Nexus_7000_Series_NX-OS_System_Management_Configuration_Guide_chapter_010100....
which makes me think it should work. In the past, I have not been able to get this to work. Does anyone have multiple destinations working on a 7K?