The debate between Hart and the Neochalcedonians is a debate between two metaphysical systems which could be described as monisms. However, Hart's is a more perennialist monism which sees a metaphysics of God-world unity as more or less accurately sketched by a metaphysics of "analogy" or "participation" (to use the most common Western terminologies) which recurs in Neoplatonism, the best Hindu and Buddhist traditions, and certain speculative (but comfortably "orthodox") forms of Christianity. There is a merely "modal" difference between God and creatures within an encompassing unity (but not identity).
Hart does not think this monism and its metaphysics needs a specifically Christological expression, or owes anything *essential* to the Christological debates after the Council of Chalcedon or the terminology developed in this period.
Hart is also eager to stay clear of Hegel and anything that introduces a *dialectical* relationship between God and the world. A broadly Vedantic or Neoplatonist model, which avoids either strict God-world identity or sharp God-world difference, in favor of the supple logic of the rhythms and intervals of analogy, between univocity and equivocity.
Jordan's monism is a specifically Christological monism. While he is an eager reader of Neoplatonic texts and quite interested in many other traditions, he takes it to be the case that the metaphysics and structure of the God-world relation is definitively disclosed in and as Christ's person.
In order to understand the God-world relation most adequately, certain terminology and metaphysical innovations developed in the debates after Chalcedon are essential, and these involve certain affirmations which cannot be made within standard models of "analogy" or "participation": including but not limited to retroactive causality, *symmetrical* and *full* interpenetration of "participant" and "participated," and a denial of the standard "limitation of act by potency."
Thee reason this metaphysics was developed was to understand how Christ could be human and divine in one undivided subject, and the terminology which proved necessary to flesh this out involved new uses of nature and hypostasis.
Jordan's approach to the God-world relation, rather than trying the "middle course" of analogy (threaded between equivocity and univocity), is dialectical, and as a result has certain affinities with and resonances with Hegel, although certainly with more nuance than how the latter's view is usually understood.
God and the world, in the abstract logic of nature, are absolutely different (a more radical *natural* distinction than allowed by analogy, one which is not merely "modal").
God and the world, however, on the concrete level of hypostasis, or real subsistence, are not just united but identical, in and as Christ.
God and the world are both more identical, and more different, but on different levels or logics, than Hart's view allows.
Christ is in himself both the identity and difference of the divine and the human, in a dialectical manner that analogy and Neoplatonism can approximate, up to a point, but cannot reach without decisively going beyond both.
Hart thinks Jordan unnecessarily ventures close to Hegel and muddies the waters of a common-denominator perennialist metaphysical consensus, while Jordan thinks Hart has not thought through the requirements of Christology and, perhaps weary of inept criticism's of classical Platonic and analogical metaphysics, has not given sufficient attention to a nuanced position which attempts to sublate its insights.
Further Reading/Listening:
https://www.academia.edu/109208834/Neochalcedonianism_Today_A_Bibliography_and_Reading_Guide
http://podcast.forgingploughshares.org/e/jordan-daniel-wood-on-his-departure-from-david-bentley-hart/
http://podcast.forgingploughshares.org/e/jordan-daniel-wood-delineates-david-bentley-hart-s-muddled-critiqe/
http://podcast.forgingploughshares.org/e/jordan-wood-on-the-logic-of-person-versus-hart-s-grounding-in-logical-abstraction/
I fall on the other side of this debate, but my only real complaint is with the way that you describe Hart’s position. For one thing, Hart is not a perennialist, and has clarified at length why he’s not a perennialist by specifically distancing himself from key perennialist ideas. (So have I.) I also think it misrepresents him to suggest that Hart’s monism requires no specifically Christological expression. The theological system articulated in You Are Gods seems an easy counterpoint to that idea. I offer these critiques while otherwise thinking you have the debate generally well-described.