Why not machine certify and hand-count verify?

Because the manual system works well and costs little.

Could have both systems for quick results on the day and verified accurate results in the longer term.

Canada already has hand-counted and verified results the same day the election occurs, in a country with a population roughly equivalent to the state of California. Adding machine counting would only add complexity and cost while producing no additional benefits.

Have the voting machine

Canada doesn't have voting machines, nor do we want them. Our ballot system is a piece of paper and a pencil. That's it. That's our whole voting "machine."

The real genius is in how the vote counting process works. Every candidate is allowed to provide a representative, often called a scrutineer, to oversee the counting process at each polling station. Scrutineers are allowed to challenge a ballot if they feel it has been attributed to the wrong candidate or should have been considered a spoiled ballot. The doors to the polling station are locked while ballots are being counted, and no one is allowed to go home until the count is complete. Basic self-interest ensures that counts are done in a timely fashion, while also ensuring that every candidate can have a representative that was part of the counting process.

Under the Canadian system, for all practical purposes it would be impossible to perpetrate election fraud. A candidate would need to somehow induce Elections Canada employees and/or volunteers at multiple polling stations to miscount ballots. They would also need to convince multiple scrutineers to turn a blind eye, scrutineers who were nominated by their opponents. Each riding typically has 4+ candidates (at minimum Liberal, Conservative, New Democrat, and Green party candidates, plus often some independent or fringe party candidates), and every single one of those candidates is allowed to provide a scrutineer at each polling station. There will be many polling stations across a single riding, so that's potentially dozens or hundreds of people that would need to be coerced or convinced to contribute to the election fraud. And that's just for one single riding.