We are aware of this problem and we sent this request to PM that there is no simple way to add a "new" server to running cluster.
If your boot medium was not damaged and you saved your configuration, you can recreate your VG, restore LVM under console and then restore your configuration using webGUI. This should allow you to add this server back to the cluster.
You can also set MPIO with physical IP for the time of reconfiguration of Failover but those are only workarounds.