McGoldrick travelled to Hannover with team-mates Joe Cordina, Kaupo Arro, debutant Lawrence Osueke and Uaine Fa having won on the road in the USA, Ukraine and Italy.
However the Commonwealth champion could not make it four victories in a row losing to Veaceslav Gojan as the Lionhearts fell to a 5-0 defeat against Germany.
The loss was Britain's fourth in their first World Series of Boxing season, all coming on the road, but it affects the standings little with a quarter-final place already secured.
McGoldrick kicked off the night with his bantamweight contest with Gojan, who just edged the judges' scorecards to hand a first defeat to his British opponent.
Cordina was next up against inaugural Youth Olympic champion Artur Bril in the lightweight bout however he was no match for the German's speed losing all five rounds.
Arro then lost to middleweight Stefan Hartel as the Germans claimed the win, his height advantage and long reach making the difference in the end.
Light heavyweight Osueke suffered a loss to Xhek Paskali on his debut in the series while Emir Ahmatovic completed a 5-0 win for Germany with a tight victory against heavyweight Fa.
Britain now welcome Ukraine and Olympic champions Vasyl Lomachenko and Oleksandr Usyk to York Hall in London for the last fixture of the regular season.