The ICU stat is tricky. They classify anyone who they don't know their vax status as non-vaxxed. Many people who come into the ICU can't speak, fill out paperwork. They are classified as non-vaxxed. By the time they recover enough to share their status they get transferred out of the ICU.
If somebody comes in the ICU with COVID symptoms, it's extremely likely that they were hospitalized earlier and thus their vaccination status is known.
If somebody comes in the ICU without non-COVID symptoms, they aren't in the statistic, in other words you need to make the probability of "unknown status" conditional on being in the ICU for COVID.
Probably the most misleading stat of them all.