The very website you link has data about exonerations[0]. From a quick look, it looks like this is about people who are still alive, not dead people found innocent after the death penalty was carried through (I'm having a hard time finding that specific datapoint). Given the exoneration data though, I'd have a hard time believing that number is 0.
EDIT: Oh boy that rabbit hole is deep. So here's some _potentially_ innocent people who have been put to death[1]. None of those are actually proven to be innocent, but there is at least some amount of evidence that spells reasonable doubt on their conviction.
[0]: https://deathpenaltyinfo.org/policy-issues/innocence
EDIT: Oh boy that rabbit hole is deep. So here's some _potentially_ innocent people who have been put to death[1]. None of those are actually proven to be innocent, but there is at least some amount of evidence that spells reasonable doubt on their conviction.
[1]: https://deathpenaltyinfo.org/policy-issues/innocence/execute...