The CVE record wasn't published yet when this particular embargo got broken. AFAIK it got published when the embargo ended, as it should. (I wasn't following anymore at that point, don't know for sure.)

What did happen is that a whole bunch of people had no clue and called the fact that "these 2 CVE IDs will be used for a PHP vulnerability" a CVE leak. Posts were going around yelling "CVE leak!" with a CVE database link that said "no information yet". Part of this is the mushed usage of "CVE" to just mean "vulnerability" rather than "CVE record". But still, quite ridiculous, and annoying. Information that CVE ID XYZ will be used for project ABC is *not* a leak. Like you say, CVE publishing matters. Getting the CVE record contents would be a leak.