Batter hits ball high off CF wall. Ball takes one bounce back toward chasing CFer whose foot accidentally comes in contact with ball that then goes over the wall. Does runner on first only get third base as a ground rule double or because the ball was initiated over the wall by the fielder, could the runner be awarded home plate?
This is covered by MLB Rules 5.05(a)(8)
5.05(a) The batter becomes a runner when
(8) Any bounding fair ball is deflected by the fielder into the stands, or over or under a fence on fair or foul territory, in which case the batter and all runners shall be entitled to advance two bases;
It's a bounding fair ball by hitting the wall. Unless the runner at first was already running and managed to get past second base before the play, then yes the runner would be awarded third.
The somewhat similar "Canseco head ball" was a fly ball when deflected, not a bounding ball and is covered by 5.05(a)(9), which can award a home run.