The manifest can be found under Feiller. The first name, Maria, is mistranscribed. The ship is the Pennsylvania which sailed in Feb. 1900, just in line with your information. The manifest says that Maria was living in Körtvelyes which most likely means Eltendorf, less likely Zahling. Both places are near Poppendorf, but they are not Poppendorf.
As to the first name Nailla, could this be a misreading of Cäcilia?
You say that Maria Feiler was an orphan. If so, who would be Josef Feiler? What does the family lore say about her passage in 1900? Did she travel with an adult who looked over her, or did she travel alone as the manifest suggests?