This is old but I see there is no answer.
The FCVI card replaces the system interconnect card. The traditional card is an IB card with Mellanox connectors and uses the traditional VIA. The FCVI card replaces the existing Interconnect card for communication between cluster heads for failover, replication, HA, memory mirroring, etc... FCVI uses VIA as the ULP of FC.
Any time you see FCVI and Metrocluster, it should be referencing this same card.
HTH... a day late 😉