Each server would have one copy of the SQLite database. Only one of the server would support writes — and those write will be replicated to the other server. Reads in the other server will be transactionally safe, but might be slightly out of date.
Is the idea you just kind of "poll" restore? That seems like a lot of extra work, if I'm reading that example correctly. It pulls down the whole database every time? Even a "small" SQLite DB (for the use cases I'm thinking of) can easily be a hundred megabytes. I don't think I'd want to poll that every few seconds.
Edit: As the blog is saying, it's mainly for single-node application so you should treat the project as a way to constantly backup your sqlite db and being able to recover from disaster.