A consistent reporting delay at least points in the right direction.
So, team panic worries more, gets tested early, has an earlier reported peak. Team virus ignores it, gets tested late, has a later reported peak.
If true, it would bump the reported case rate up for vaccinated, because they’d be catching more of the mild cases.
Not sure if it is the right time scale. Omicron has a pretty short incubation period. That makes it hard to squeeze in a week long delay without the patient recovering and skipping the test entirely. If that is happening, the unvax case rate would be underreported, and the unvax hospitalization/case ratio would be over estimated. (because you are underestimating the denominator.)