There are more settled cases for flu vaccines because more people get flu shots than the others.

What we really need to see is the rate of injury per million vaccinations. If ten million people get the flu vaccine, and there are five serious adverse effects (rate of 0.5 per million), and a thousand people get another vaccine, and there is one serious adverse effect (rate of 1000 per million), its the second which is way more dangerous even though the raw number of injuries is less.

Without knowing the rate of injuries, the raw numbers are meaningless.

Also, keep in mind that vaccine compensation in the US is theoretically on a "no fault" basis, that is, you don't have to prove the vaccine caused the injury. The reality is not that good: vaccine compensation in the US is pretty ugly, with plenty of wriggle room for the authorities to deny compensation to those who genuinely deserve it. But better than, say, North Korea.

But to a first approximation, we can assume that in most of those cases, the person only needs to prove that

1. an injury occurred;
2. it occurred within some period of time after the vaccine; and
3. its the kind of injury which could plausibly have been caused by the vaccine.

So not every compensated injury will have been caused by the vaccine. Unvaccinated people get diseases like Guillain-Barré Syndrome too.

Suppose that out of a million unvaccinated people, two will get GBS. And out of a million vaccinated people, three will get GBS. Then we can guess that two of those cases of GBS in the vaccinated people would have occurred regardless of the vaccine, but of course we have no way of knowing which two. So a "no fault" scheme will compensate all three, even though probably only one was caused by the vaccine.

It takes some really clever medical sleuthing to work out the rate of actual injuries caused by the vaccines, and the honest truth is that in most cases, we really cannot tell which injuries and side-effects were caused by the vaccine and which would have happened anyway. Medicine is not an exact science.

Here's an analogy for you: I buy insurance for my new home, and the very next day it burns down. Was it fraud? Just because my house burned down a day after I bought insurance, doesn't mean I was committing fraud. I just got unlucky.