I checked the wiki thoroughly, but it doesn't have a detailed breakdown of who played with the 1st- and 2nd-team units in the Packers' preseason opener. The wiki covers the Packers' overall outlook, depth chart, and training camp developments (like Aaron Banks landing on PUP and Christian Watson's extension), but specific preseason game-by-game snap counts or unit assignments aren't documented here.
You might find that info in a game recap or box score from the Packers' preseason opener — something like a local beat reporter's article or the team's official site would typically break down which starters/backups played.