I'm not sure that I see these matters related in any way. For what it's worth, I don't consider myself Klinean. I have a fair library, and not one book by Kline. Probably a gap I should fill...
Republication or re-expression, restatement, etc.--this concept does not originate with Kline. What I think the OPC report dealing with republication does is make clear that Kline's views on the nature of republication can be read in two directions, "substantively" and "administratively." His strongest critics make a case that Kline advocated some sort of substantive republication at some point in his career. The OPC report (rightly) indicates that is the wrong direction, confessionally speaking.
The ANE treaty-form I summarize and condense here (I freely admit my inadequacy to the task) to the best of my knowledge as: preamble, parties, stipulations, sanctions. It is a structure analytically developed from studying ancient documents; it isn't as if there was an ancient U.N. that imposed a "template" that all the local nations and empires had to follow. I fail to see how structure impacts the question.
There is one twist on the theory: that the treaty-form has two main expressions, bilateral and unilateral, or a treaty of mutual obligations and one that was clearly suzerain-vassal, where the obligations stated are one-sided. As I understand the matter, some have said that the former is closer to the Mosaic covenant, the latter nearer to Abrahamic (one sided). I personally don't think that analysis is good. Yes, Abraham's covenant was one-sided; the obligations are self-imposed by God; and I think it is asking too much of a theory to then flip the theory (theory upon a theory). The general theory is better, allowing for a variety of expressions of one concept.
The CoW is drawn in the simplest of terms in Scripture: do and live is the sum of it. Eden is the setting, God imposes it, man is the recipient, "do not eat the TKGE," "or die." There, I describe the CoW in four parts corresponding to the ANE model. You can do something like this with all covenants of Scripture. The existing ANE treaty concept shows primarily that the testimony of Scripture to the existence of such arrangements has not been anachronistically imposed by a later author on the past, whether on the putative Exodus era or on the patriarchs' era.