1/19/2018 If Journey to Eternity and the enchanted creature are both put into graveyards at the same time, Journey to Eternity’s ability will return both to the battlefield.
And the reasoning behind it is, that "dies" triggers, and leaves-the-battlefield triggers in general, look at the game state right before the event to determine if they should trigger. This is an exception to the default, that trigger conditions are checked after the event. Since JtE was attached to the creature right before both got destroyed, both get to return.
edit:
Additionally, the game can find the Journey in the graveyard due to this rule:
603.6e Some Auras have triggered abilities that trigger on the enchanted permanent leaving the battlefield. These triggered abilities can find the new object that permanent card became in the zone it moved to; they can also find the new object the Aura card became in its owner’s graveyard after state-based actions have been checked. See rule 400.7.
And the reasoning behind it is, that "dies" triggers, and leaves-the-battlefield triggers in general, look at the game state right before the event to determine if they should trigger. This is an exception to the default, that trigger conditions are checked after the event. Since JtE was attached to the creature right before both got destroyed, both get to return.
edit:
Additionally, the game can find the Journey in the graveyard due to this rule:
Former Rules Advisor
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