That's one way of stating the issue. The simpler way is, "Who makes the decision when faithful Christians disagree about something important?"
If by being "ecumenical," the good cardinal means I get to decide and he will agree to accept my decision, I am all for it. But I suspect that's not what he means.
He does think that, and so does his pope. What neither of them believe is the "ecumenism of return" to the Catholic Church.