But they also aren't currently told explicitly to not convict unless they are positive that no new evidence could come out that would overturn the conviction.

Nor should they be. Juries aren't fortune tellers, they decide based on the evidence presented not on evidence not presented.

Perhaps the disconnect is that I hold a higher standard for sentencing than you do.

No the disconnect is you see no shades of gray. In your mind if somebody is guilty then they are totally guilty. You said it yourself, the second decision of the death penalty is "superfluous" because there's no difference to you.

So what scenario did you come up with where you would rightfully convict, then later new evidence shows they were actually innocent? I don't know what your personal standard is so only you can answer that.

I doubt that you can or will so here's one for me. If the defendant was proven in the area, had motive, no alibi, and his DNA was found at the scene without explanation then I would convict. Later if it turned out the prosecution withheld video evidence showing the defendant somewhere else then I didn't make a mistake (the prosecutor did), but the verdict was still wrong. It's not reasonable to acquit by assuming the prosecution did withhold evidence, but it is reasonable to consider it a possibility especially since that has happened quite often.

So I wouldn't vote to execute based on that evidence because while it's beyond reasonable doubt it's not beyond all doubt. But I would if they had bodycam footage of defendant being caught red handed and it was a capital offense because then there's no reasonable possibility they got the wrong man.

According to you, in this scenario you would find not guilty because means/motive/opportunity with DNA isn't absolute proof. That makes you an OJ Simpson juror.