We also bumped into another situation were we could talk to only one of the nodes on the source cluster. It turns out that it was a bug in 9.2.
Netapp Tech Support:
The error "snapmirror license not available" is due to an OnCommand/API bug. It occurs when an attempt to create a SnapMirror relationship within System Manager while having non-1500 MTUs set.
To resolve the issue, create and initialize the relationship on the destination cluster command-line and then you will be able to resume normal operations/management on the GUI moving forward.