AF Corse driver Lawson set the first benchmark of the session with a 1m32.584s before Maximilian Gotz sent a 1m32.563s in HRT Mercedes to snatch the top spot away from the Kiwi.
Lawson responded with a 1m32.168s and this playing time proved to be just enough to require a second pole in the last three qualifying sessions where none of his rivals could match his time in the second race.
The 19-year-old actually went even faster on his last flyer after putting purple times in sectors 1 and 2, but chose to interrupt the lap when it was clear that his previous time would be good enough for the top spot on the net.
Double DTM champion Wittmann was the closest challenger to Lawson in the venerable BMW M6 GT3 and posted a time of 1m32.202s to secure a place in the front row.
Gotz eventually finished with the third fastest after failing to match Lawson in the other races, finishing 0.121s down on the Kiwi with a time of 1m32.323s.
Philip Ellis was fourth for Team Winward, another 0.027 after his Mercedes teammate Gotz, while championship leader Kelvin van der Linde qualified as the best Audi driver in fifth place.
The abbot Sportsline driver wheeled Ellis on his outlap, forcing him to get to the pits after a new rear left tire with just two minutes left of the session.
Last year’s runner-up Nico Muller enjoyed improved fortunes after a difficult run of races in leading Team Rosberg Audi entrance, securing his best starting position since Zolder in sixth place.
Seventh place went to Vincent Abril in the second HRT Mercedes, ahead of Sheldon van der Linde in the Rowe Racing BMW.
The top 10 was rounded off by Mercedes drivers Arjun Maini (GetSpeed) and Maximilian Buhk (Mucke Motorsport).
Several drivers lost their best laps to track violation limits right at the end of the session and fell to the second half of the net.
Ex-F1 driver Christian Klien had originally qualified as fifth on his last race weekend with the JP Motorsport McLaren team, but he was eventually relegated to 16th place. Red Bulls Alex Albon also fell from sixth to 14th, while factory Lamborghini driver Mirko Bortolotti fell to 12th.
However, Bortolotti beat his T3 Motorsport teammates on his guest appearance, with Esteban Muth and Esmee Hawkey only finishing 18th and 20th in their Huracan GT3s.
The qualifier was red-marked with less than six minutes left on the clock when Dev Gore crashed at the exit from turn 7 and suffered injury on the right rear of his Team Rosberg Audi.