If that structure is sola scriptura, yes - for certain "One Lord, one faith, one baptism" cannot exist with it.
However if the well-delineated bastion is the pillar and foundation of the truth - which is the church of the living God founded and headed by Christ and led by the Holy Spirit, then it does not, and has not, crumbled and the gates of hades shall not prevail against it.
You then contend Scripture is incomplete, and subsequent revelations have been pronounced with equal gravitas.
Please enumerate some of these, and how we know they are not just the rantings of mere mortals.
And how, pray tell, is “one Lord, one faith, one baptism” at odds with Scripture sans additives?