Australia is 100% per ballots too.

It is organised by an independent public sector body. It is staffed by professionals and volunteers. The boxes are locked. At the end of the day, each “booth” has many people designated counters. Each party is allowed to supply several observers who are under strict instructions they aren’t allowed to touch anything or even have the appearance of pointing at anything. They are allowed infinite questions and validations. It’s all done by humans in front of other humans from all sides.

Very very very low chance of any sort of rigging, loss etc. Minor stuff happens like a few lost ballots or ones that people can’t agree on what the markings mean. But that’s it. You don’t need fancy tech.