Most software people I know aren't particularly persuasive. One trait noticeably missing among them is the ability to simplify a complex topic without losing too much relevant information.

But even if some are, ways exist to undermine an expert's credibility about a complex topic.

For example, when Robert Oppenheimer began warning people about the dangers of nuclear war, the attacks came. Once the government felt comfortable enough with Edward Teller, it could proceed with revoking Oppenheimer's security clearance.

That said, not sure a paper receipt actually helps because it's certainly possible for a voting machine to spit out a receipt, then change whatever data the receipt was supposed to capture. And unless the change was drastic and massive (e.g. Trump wins California) then it will probably go undetected.