I'm sorry about the multiple posts, I didn't know which was the most appropriate forum, as the information I had was conflicting and overlapping.
The two women I'm searching for are Caroline Lisette (she was known as Lisette) Schiemann, nee Buchmann. She was born in Kraftshagen, East Prussia in approximately 1828 (based on LDS films of her age at her marriage. She married Wilhelm Gottlieb (went by Gottlieb)Schiemann in Albrechtsdorf East Prussia. They took their family to Volhynia, Russia in approximately 1870. Gottlieb died in approximately 1892 or 1893. At that time, Lisette emigrated to the USA with several of her sons and their families, landing at Ellis Island (confirmed) in August 1893. The stated destination on their immigration record lists Stiles, Wisconsin.
Hulda Schiemann was born in May 1877 in Volhynia to one of Lisette's sons, Johann Herrmann (went by Herrmann) and his first wife, Emilie Schulz. In 1893, she travelled to the US with her grandmother and uncles and their families.
Nothing after the Ellis Island record has been found about Lisette. Hulda is confirmed in Milwaukee on the 1900 census. The rest of the family they arrived with seem to have headed almost directly to Oregon, as evidenced by children's births and censuses. Nothing is known regarding why Hulda didn't go with them, and there are no further records of Hulda.