Here the typesetter for the 1849 LDS edition accidentally set Homer in place of the correct Omer. The correct name was restored in the subsequent LDS edition (in 1852). The name Homer would have been known to the typesetter, but not Omer, which explains the error. Elsewhere in the book of Ether, 14 instances of Omer were maintained without change in the 1849 edition.
Summary: Maintain the name Omer in Ether 8:11 and elsewhere in the book of Ether.