Not really that confusing. The study was on hospitalized covid patients. The 99.7% is referring to the results of that study.
They also mention that during the study they collected data on the vaccination rate of the hospital employees at the time likely because hospital employees often come in contact with hospitalized patients.
The Cleveland Clinic found that 99.7% of its employees who were infected with the coronavirus were not vaccinated, and 0.3% of infections occurred in those who were fully vaccinated.
The Cleveland Clinic on Tuesday released a study showing that 99.75% of patients hospitalized with COVID-19 between Jan. 1 and April 13 were not fully vaccinated, according to data provided to Axios.
OK, so in order to believe that you'd also have to believe that the number was exactly the same for each group, 99.7%
That's almost statistically impossible. You buying that?
What are the chances that two groups of people would show the same thing down to the decimal point? Think about that
This is the physician they mentioned in the article from Cleveland clinics pulmonologist group.Cleveland Clinic study shows employees with COVID-19 vaccine protected
A little more clear of a report. But I still can’t find a link to the actual study. But it looks as though it is the same number for both groups.