Nudelmann is standing watch on the bridge at X: -196 Y: -10 that leads through Baldur's Gate[1]. He watches over the queue of residents trying to make their way into the Upper City.
Having received orders to not let anyone into the Upper City, Nudelmann and his fellows: Fist Grassley, Fist Wizard Hartlebury, Fist Magnolia and Fist Qirahe, accompanied by a Steel Watcher, are trying to keep the queue orderly and prevent anyone from entering. If spoken to, Nudelmann, just as most other guards in the cordon, takes the player character for a citizen who tries to make their way through the gate ahead of the queue.
If the party return to the city after acquiring all Netherstones, three infected refugees near the queue transform into Mind Flayers and attack the bypassers. Nudelmann is Surprised, but fights alongside the party. Once the Mind Flayers are dead, he and all the Fists around run away to warn their superiors, before completely vanishing from the game once far enough.