Its pretty simple really...
If you have marked your ball and it moves afterwards, just replace it. Whether you accidentally bumped it, the ground caused it, the wind caused, the rain caused it, etc. you just put the ball back to the original spot and play on.
No need to get penalized for a ball oscillating, that's ridiculous. If you accidentally bump the ball returning the putter after a practice stroke, there should be no penalty as no advantage was given.
If the player clearly didn't make an attempted stroke on the ball, just replace it and carry on.