5-man party in 4-man dungeon

Character Name: Komeko Kikumaru

World: WP dungeon.

Class/Level: Lvl 50 White Mage.

In-Game Time: 7 to 8 p.m server time.

Steps:
1: I unmarked E and marked F in Duty Finder, as well as marked "Join Party in Progress"
2: I marked the following dungeons: Aurum Vale, Wanderer's Palace, Castrum Meridianum, Praetorium, Amdapor Keep.
3: I entered Wanderer's Palace in-progress and found myself in a party two dps and two tanks, one being a PLD and the other a WAR.

Screenshots without names and interface: http://imgur.com/a/K9QdE

Note: The cutscene after we defeated the Tonberry king only showed four of us, not five - and only three names showed up in the commendation list.