The biggest reason why this can't be Oden (all assuming that Oda didn't just completely lose the plot): He has his two swords with him.
We know that one can only travel forward in time though and we also know the whereabouts of the real Enma and Ame no Habakiri in the current timeline (Zoro has Enma, Hyori has Ame no Habakiri).
With his "you can only move forward in time" restriction, Oda basically eliminated the possibility of two Enmas/Ame no Habakiris existing in the same timeline.
Therefore we can conclude that those two swords, that the "Oden" of the last panel wears, are fake swords.
This Oden is an impostor.