A volume deleted in the absence of one of the peers wouldn't be removed from the cluster's list of volumes. This is because the 'import' logic of peers that rejoin the cluster is not capable of differentiating between volumes deleted and volumes added in the absence of the other (conflicting) peers.
For now, we intend to manually detect it which may involve analysing cli cmd logs to get the cluster view of the volumes that 'ought' to be present. Once we arrive at this picture, we could use volume-sync to reconcile the skewed view of volumes in the cluster.
Bricks added/deleted to a volume while some of the peers were down/unreachable, are 'imported' as they rejoin the cluster.