9 to 28 times? I figured “excess events per 100,000” means if the control rate is e.g. 200 events per 100,000 then the observed rate after vaccination was 209 to 228.
They also give a ratio, which could also be interesting, and which you can't deduce from the excess events without knowing the number of events in the reference group.
So if that is virtually no risk, so is 20 cases of myocarditis (that aren't all lethal) per 100,000.
(I used 6100 from https://www.statista.com/statistics/1191568/reported-deaths-... divided by 53 million to get 10/100,00).