Just to be clear on that, none of these games were made with jMonkeyEngine. Aion for example was made with the cry engine.
There was an attempt from ncsoft to use jme for a game and they even hired 2 of the core developers at some point. This was at the time of JME2 and in the end the project got cancelled. JME3 is vastly different from JME2 and was made by a completely different team.