Is the taxi route omitted in low visibility (LVP)?
It has nothing to do with LVP, but with the fact that there are standard routes at Schiphol to the main piers;

From the AIP AD 2.1 (EHAM) section 2.1:


  Aircraft shall comply with the standard taxi routings to and from the stands as depicted on AD 2.EHAM-GMC. Deviations from the standard taxi routings will be given timely to the pilot by Schiphol Ground.


The AD 2.EHAM-GMC (Ground Movement Chart) shows the following in the legend:



Late at night, when there is almost no traffic, there is no need to hold aircraft or deviate from the standard route.

The crew is Dutch, they are at their home based, so they are well aware of the routing. So ATC only gives their stand, knowing they will find their way.

There's a double taxiway almost fully around the central terminal area. The outer ring is counterclockwise, the inner ring is for clockwise traffic. The exit for RWY 06 leads straight onto the counter clockwise taxiway. From there you can follow that until A10, which leads you to the D5 gate. There is basically no other way.