One dungeon should be for sure expected and this is "Return to Delera's Tomb" this one is level 6 and you need to enter it before you can enter the last part of the chain that is level 8.
Another good reason here is that this is a nonhostile dungeon with no risk to die beside you find a way for your character to suicide, you walk in and out and it is done which means that there is no reason at all for the 4 levels rule.
Another Dungeon is "Hall of the Mark", the level 1 quest to activate the dragonmark for the server and to receive a free feat change at Fred.
similar reasons cause it would be no problem at all to except this one