Careful - do we know the crew knew they had gone into the grass before taking off?
There is no way you would miss this excursion.
It happened at A, a 90° taxiway at the end of 27, just where A joins 27 (so way past the CAT1 hp). There is a perfectly good lead on / lead off line to keep you out of trouble, but the FR turned hard
right to get the last couple of feet of TORA (27 is off to your left). Wheels 3 and 4 both came off the right of the taxiway and back on to the edge of the runway, leaving 2 big trenches that look about half a wheel radius deep.