You can loot Ferumbras hat from the Ferumbras ascendant Quest , on that Ferumbras the drop of ferumbras hat is random and not based on the damage/heal/damageBlocked. But in the Ferumbras that appears on Raid in the castle that is based on who wins it so in that case you will need to be the one who deals more damage / heals more / block more damage from feru.. In that case is really hard to loot it.
In the case of Morgaroth.. if you are enough level to win it you can loot it , for example the other day in Secura a lvl 500RP won the Morgaroth because he hit the Morgaroth more times since he spawned , think that Morgaroth and Ferumbras (raid) only last like 5 seconds now...