Has Rome dogmatically defined all of Scripture yet?
Which ECFs is the Roman Catholic to rely upon? The ones who agree with Rome or who disagree with Rome? What does the Roman Catholic do when the ECFs are in contradiction of Roman Catholic theology?
The ecumenical councils of Florence (in the 15th century) and Trent (in the 16th) defined the canon of Scripture. Is that what you meant?
It would be impossible, and silly, and also very harmful to attempt to infallibly define all possible meanings of every passage in Scripture, the way some silly Protestant apologists try to take Rome to task for not doing. You know, or at least you should, that Scripture has many layers and nuances of meaning and nobody can exhaustively define all possible meanings, senses, typology, and implications of even one verse.
The ones who agree with Rome or who disagree with Rome?
The real problem is that after you take 100 Church fathers and then eliminate all of those who agreed with the "reformers" and taught recognizably Protestant doctrine ... you are still left with 100 Church fathers.