I think both can be true, but we do have more weighted evidence of his greed. And his betrayal f Jesus for silver is typologically consistent with Judah's betrayal of Joseph and subsequently selling him to Ishmaelite traders for a profit.
Discussion
Biblical types are awesome. I think that strikes at the heart of it. Fundamentally, I think his betrayal is a replaying of Judah and Joseph, Cain and Abel, etc. He destroyed his brother because he could not master the sin that was crouching behind him.
Yeah! Typology is one of my favorite interpretative methods for understanding Scripture.
Along these lines, Judas is also a type of Absalom. The former betrays David (driving him out of Jerusalem) and dies by hanging on a tree. The latter betrays the heir of the throne of David and dies by hanging on a tree.