Engel made a bungled bid to pass the ultimately victorious SunEnergy1 Mercedes-AMG with just over three quarters of an hour remaining, turning around Jules Gounon at The Chase on Lap 300.
The GruppeM Racing Mercdes-AMG emerged with the lead but it was a fleeting spell back at the front of the field once stewards issued a drive-through penalty.
The German dropped to third once he transited the lane and charged home thereafter, but came up half a second shy of the Manthey EMA Porsche at the chequered flag.
GruppeM had only been put in that position when it had to serve a longer final pit stop in order to fit a new modem to address a data logger issue.
The incident with Car #75 was an awkward one considering it involved two Mercedes, and hence driving crews which are intermingled through the German marque's programmes, leading to Gounon saying “sorry” to Engel.
The German said, “As Jules said, we're all good friends, Jules and Kenny [Habul] and Luca [Stolz], so, very, very happy for them.
“At the same time, obviously extremely disappointing for us.
“It was our race, we had everything under control until we were requested to add a data logger for last pit stop.
“That sort of threw us behind them and then, from there on, I knew I had to make a move, and they were just so quick in a straight that even though I had fresh tyres and good exits, it was hard to keep up in the straight.
“So, I went for the move and it's unfortunate we came together.
“I respect to decision Race Control took and I've got nothing more to say.”
When asked by Speedcafe.com to clarify if that respect meant that Engel agreed with the decision or not, he simply responded, “I won't comment on that.”
Raffaele Marciello, GruppeM's other steerer, attended the post-race press conference with Engel and Grenier, as is protocol, but opted not to take questions.
“I promised to the team that I will not create any messy media so today I do not speak much,” he said when asked to talk through another near-miss in the Mount Panorama enduro.
While GruppeM did salvage a podium, the result was a comedown from the jubilant scenes of 24 hours earlier, when Engel took pole position with a qualifying record 2:00.8819s.