If you are going to make the spaetzle, do them first. Mix all the ingredients together in a bowl. Bring a large pot of water to a boil and salt it well. Fill the spätzle maker with the batter, which will be goopy and sticky, and run it over the boiling water. Do this is batches, skimming off the spaetzle as they float to the top. Put the finished spaetzle onto a baking sheet and coat with a little oil. Set them aside.
To grill the trout, coat them in oil and salt them well. Set them out at room temperature for 20 minutes, while you make the fire for the grill. Make very sure of two things: 1), that your grill grates are spotlessly clean -- foods stick to gunk on the grill, not the grill itself; and 2) that the grill grates are very hot. Right before you put the trout on the grill, wad up a piece of paper towel and, using tongs, wipe down the grill grates. Put the trout on the grill.
Let the trout cook until they are nicely browned, even charred a little bit. How long? At least 5 minutes, and maybe up to 10, depending on how hot your grill is. As they cook, paint them with the roasted pumpkinseed oil, or some other good oil you like. Use a metal spatula -- I highly recommend using a fish spatula because they are very thin and flexible -- and test to see if the fish comes away easily from the grill. It will when it's ready. If it still wants to stick, let it cook a little longer. When you are ready to turn the fish, slip the spatula under the fish and, using your other hand to steady it, flip the trout. Do this only once. Grill on the other side until the trout comes away from the grill easily, again, about 5 to 10 minutes.
When you flip the trout, start the greens in a large saute pan set over high heat. Add the chopped greens and saute for a minute or two, until they wilt. Add the spätzle and stir-fry them for a couple minutes. Turn off the heat and sprinkle salt and black pepper over them.
To serve, put some of the greens and spätzle on everyone's plate, then a trout. Drizzle a little of the roasted pumpkinseed oil over everything, then splash everything with a little freshly squeezed lemon or malt vinegar.