Medicare's Two-Midnight Rule - relevant admission time stamp

[BenGIT94]

I am currently working with MIMIC-IV ED / MIMIC-IV to answer a specific question regarding the two-midnight rule of Medicare. Simplified, the two-midnight rule requires the hospital to keep patients at least two midnights in the hospital to bill them as inpatient (read e.g. https://www.cms.gov/research-statistics-data-and-systems/monitoring-programs/medical-review/downloads/qasforwebsiteposting_110413-v2-clean.pdf).

The main question is, though: Which time stamp does BIDMC use to determine when a patient was admitted? Medicare writes that the determination of the 2-midnight rule includes "treatments in the emergency department, and procedures provided in the operating room or other treatment area. From the medical review perspective, while the time the beneficiary spent as a hospital outpatient before the beneficiary was formally admitted as an inpatient pursuant to the physician order will not be considered inpatient time, it will be considered during the medical review process for purposes of determining whether the 2-midnight benchmark was met and, therefore, whether payment for the admission is generally appropriate under Medicare Part A".

So, specifically, assume the following case: patient enters the ED at 23:21 ("edregtime" in MIMIC-IV-ED). Patient gets vital signs checked at 23:43 and receives a medication in the ED at 23:57. The patient gets officially admitted as inpatient ("admittime" in MIMIC-IV) at 0:05. Now, 24 hours later at 00:05, patient gets discharged again. Did the patient meet the required 2 midnights, or does the first midnight not count because the patient was admitted as inpatient just after midnight? Which time stamp is the relevant one for the two-midnight rule here from a Medicare perspective/which does BIDMC consider when discharging patients in light of the two-midnight rule?