Get ready for some serious legalese. But if you follow the reasoning, you will be impressed with the extent of wargaming that has been invested in the safeguards of the Compact for America approach to Article V.
1) Because the Compact has no substantive effect until 38 states join it, the formation of the Compact does not cause a cognizable injury needed for standing to sue by Congress or non-member states until such time as a super-supermajority of states stand behind its terms and conditions; in combination with its sunset date (self-repeal 7 years after first enactment), this ensures a massive and contemporaneous political consensus will be forged around its terms. This means that going along with its terms will be perceived as more advantageous by ambitious politicians than suing over or violating its terms. Further, politicians opposed to the Compact’s terms would have more legitimacy attempting to delay proceedings at the convention until the 24 hour adjournment clock runs out (the Compact requires an up or down vote within 24 hours after commencement of convention proceedings), than to violate the Compact’s terms and conditions directly by proposing one or more different amendments. Furthermore, the prospect of the Compact approach to Article V having dual use, like a ballot measure, will incentivize many opponents to the merits of the initial payload to play along with the process. For these reasons, it is exceedingly unlikely that the Compact-organized convention would be viewed or serve as fertile ground for a runaway convention.
2) In the event of litigation, if the Court rules the Tenth Amendment governs the interpretation of Article V, as it should under current precedent, then the lack of any prohibition on the states from using their plenary governing power to control and direct an Article V convention combined with the lack of any delegation of such power to Congress, provides the legal basis for the states controlling and directing the Article V convention process through a Compact that limits the convention to a 24 hour up or down vote on a specified amendment.
3) If the Tenth Amendment is ruled not to govern the interpretation of Article V, then the text of Article V, interpreted in light of the contemporaneous understanding of its terms, compels the conclusion that the states control and direct the Article V convention through the provisions of their "application," which triggers Congress’ mandatory call duty (the nested application in the Compact would likely be interpreted as incorporating the terms and conditions of the Compact as a whole because it is an integrated instrument).
4) If Congress is erroneously deemed to control the Article V convention through its call power, the Compact ensures that no member state may attend the convention if Congress deviates from the Compact’s terms and conditions in its call, thus depriving it of a quorum by population or state-by-state representation, until such time as Congress is co-opted into yielding or adopting the Compact’s terms and conditions in its call for the convention. The sunset date ensures that the Compact will eventually self-repeal in the event of a lingering standoff or protracted litigation. And if Congress passes a resolution calling the convention in accordance with the Compact (as is the goal), then it will have yielded expressly to the terms and conditions of the Compact and there will be no one with standing to advance Congress’ claim to control the Article V convention.
5) If the attendees of the Article V convention are erroneously deemed to have the independent and autonomous power to control the Article V convention, those attendees will have every narrowly self-interested political incentive to follow the terms and conditions of the Compact because of the massing of political will behind those terms and conditions in a short period of time (due to the sunset provision), and the fact that a supermajority of delegates will likely be governors or presiding officers of legislatures in the states that passed the Compact and personally committed to its terms.
6) If non-member states object to being governed by the rule of one-state, one-vote, and instead argue for proportionate voting representation under the 14th Amendment, the argument should fail even if an analogy of an Article V convention to the non-proportionate voting rules of the Electoral College or the Senate fails (which is unlikely) because the Compact’s requirement that at least 38 states adopt its terms before a convention call is triggered ensures: a) that member states will have a majority of delegates even under proportionate representation, and thus the proposal or refusal to propose the contemplated amendment will not turn on whether voting is by state or by population, and therefore non-member states cannot claim any cognizable injury from or standing to sue over the one-state, one-vote rule; and b) the one-state/one-vote rule would be regarded under current precedent as a rough approximation of proportionate voting because it will have been adopted by states likely representing a majority of the country’s population.
7) No matter what happens at the convention, every member state (38+) would be contractually bound not to ratify any amendment it generates if the Compact’s specified convention rules are not followed or if the amendment proposed deviates from what is contemplated in the Compact. So long as at least 13 member states hewed to their contractual obligation not to ratify a runaway proposal, the Compact would self-repeal and all of its proceedings will be deemed void ab initio if the contemplated BBA were not ratified by April 12, 2021, thus ensuring that a runaway convention or amendment proposal loses all legal legitimacy if those terms are enforced.
8) And even if all of these provisions somehow mysteriously had no effect, the constitutional text of Article V itself still empowers Congress to intercede and refuse to refer for ratification rogue amendments and even if Congress referred out rogue amendments, Article V still requires 38 states to ratify any rogue amendment that might be generated. All it would take is one well-placed Committee chair in Congress or in just 12 chambers out of 99 to kill the ratification of any rogue proposal. It is completely implausible that ratification would happen with so much obvious and flagrant lawlessness that would be attending any rogue amendment that might somehow be proposed by a Compact-organized convention.