Yeah this has been bothering me for some time now. Ogre is one of my favourite bosses in the Tekken series and his two forms (True Ogre and Monsterous Ogre) were one of those great moments in Tekken when you beat them on the hardest difficulty. But after his return in Devil Within and that mysterious devil like creature in the container in Russia, I don't believe Ogre is fully dead...yet.
Of course the thing in Russia could have been Devil Jin, Azazel or even Devil himself or another devil, it doesn't mean it can't be Ogre. Devil Jin killed him in Devil Within however there is still samples of the Ogre gene left and there are also other means of resurrecting him as well. Devil Kazuya could be a means of bringing him back (mainly because of what happened in Tekken 4) but its also not. Whilst not explained in the series, Ogre could come back as a spirit (he's a god, he can't be destroyed fully) and of course the contemplation from the rumours created in Tekken 5 and Devil Within, there could be another Ogre.
Mokujin (if you've seen Blood Vengeance) has many mysterious powers that may not all have been revealed yet but from what I've seen if there is some form of DNA of Ogre still remaining, he could take over Mokujin's body and use that as a host body.
Either way I think its time something is done about Ogre because I don't fully believe Ogre's gone in the series...yet. What theory or opinion do you have?