And I'm agreeing with you. It cannot mean to become gods in the sense of polytheism (which would be idolatry) or in the sense of being merging and being dissolved into God (which would be blasphemy.)
Therefore, the only orthodox way "becoming gods" can be interpreted in this context, is to partner by a participation in the *nature* of God.
Do you care to comment on this very important distinction between "person" and "nature"?
CCC 460 The Word became flesh to make us "partakers of the divine nature": "For this is why the Word became man, and the Son of God became the Son of man: so that man, by entering into communion with the Word and thus receiving divine sonship, might become a son of God." "For the Son of God became man so that we might become God." "The only-begotten Son of God, wanting to make us sharers in his divinity, assumed our nature, so that he, made man, might make men gods."
Now I dont don't need to analyse or twist or contort those words they speak for themselves. I would direct your attention to the first instance. that we might become (capitol G) God.