That’s honestly the smallest part of election validation. How do you know everything was recorded to the log correctly or at all? In other words, the actual “election” part where you verify voters and collect results, which has nothing to do with blockchain. But even if that is all done right, how is the blockchain itself being run? Blockchain data is only as trustworthy as the systems doing the verification. A centralized blockchain is no more trustworthy than a centralized database of any kind. And a distributed blockchain has its own attack vectors. Rubbing blockchain on it is not a security solution.
If I am given a voterID, let's say an address from which I cast my vote. I can look at my vote on the chain to ensure it was cast correctly forever from that point forward. The node software would ideally be open source and publicly available. A full node could be run at each voting site, and potentially by citizens themselves even. You could run one to make the voting process even more secure.
A decentralized blockchain is far more trustworthy than a centralized database in this scenario. Say Russia controls the centralized voting database, they can just edit whatever value they want to say "Putin" and call it a day. It's not public. No one can verify their vote. It's under the control of one party. The entire point of decentralization is to ensure there is public consensus among multiple parties.
There are other discussions about how to allow or incentivize citizens to run nodes, mitigate lost or stolen IDs/private keys, prevent against spam attacks, etc...but it sounds like you aren't even open to discussing those because you equate the word "blockchain" with "snake oil".
It is secure, even if its centralized, because you will be able to see if your vote counted or not. At the end of the election, there will be a digital artifact, that will allow you to cryptographically prove whether or not your vote was tallied.
