According to these plans
, the turbolift doesn't open up onto the dorsal deck at all! Or possibly straight into the intermix room, the diagram isn't clear...
Maybe you could go with that direction? The dorsal is such an awkward space anyway
Shane Johnson got around the issue by having the turboshaft progress down the rear of the dorsal, as shown here
. The shaft would skirt around the impulse engines (I guess) before it entered the vertical shaft and began its descent. The stepped path is not as elegant as a single vertical one, but it does leave plenty of space for exit points!