Author here. I've tried to keep the article as apolitical as possible, while giving some context to provide the setting. Anyway, I'm very interested in knowing if the used crypto is sound or not, and stirring a discussion around possible alternative approaches. Ask me anything if you want to know further!
The only information you would get by knowing some of that data is where somebody is supposed to vote. An information you can already infer from the Zip code. There are, at most, four possible voting sites for each zip code. In some (several) small/medium villages there is only one voting site, so, not to much to learn from decrypting.
Besides, the census (voting places) information is usually (in normal elections), placed (via paper printed listings) on voting places. And there there is more information (full name, for example).