They probably drove into the crater because they did not see it.  Looking at the shadow angle and the direction of the tracks, they approached the crater from directly up-sun.  Between the zero-phase angle for the sun and the retro-reflective nature of the lunar regolith (heiligenschein), I seriously doubt he had any idea the crater was there before he hit it.  It is entirely possible that he stopped right there because the jolt gave him a 'whoa, enough of that' moment.