On my PB631, genuine PB firmware, the binaries are indeed in /ebrmain/bin/. You can inspect the system directories if you installed a terminal app, or ssh, or rooted. If the Vivlio firmware doesn't include them, I'm not sure just launching a copied binary would do. It may well be that they call libraries which aren't in the vivlio either, or depend on particular file locations.
If it helps, I attach my sudoku.app.
You may also want to check
this and the
Vlasovsoft suite, there are other sources for games.