Place potatoes into a large pot and cover with salted water; bring to a boil. Reduce heat to medium-low and simmer until tender, about 20 minutes. Drain, cool, and cut potatoes into bite-size pieces.
Combine celery, green onion, carrots, bell peppers, and olives, in a large bowl. Stir mashed eggs, mayonnaise, mustard, pickles, salad seasoning mix, and dill seasoning in another bowl; season with salt and pepper. Stir egg mixture and potatoes into vegetable mixture. Add pickle juice and mix until creamy.