Osmundsen/Tvitækken

My great grandfather left Rauland Telemark in 1860 as Aslak Osmundsen Tvitækken. He also had a brother Knute that left in 1861. On a passenger list, the bark AMELIA, that left Porsgrunn on April 20, 1860, there is a Aslak Osmundsen Tvedteggen. Are these the same farms? Not knowing pronunications, I can't be sure. I have no other information on their family, only the NHDC 1865 census as to who their father might be, but have not been able to accurately identify anyone. It shows Osmund Johnsen as being born in 1804, Knute was born in 1824 and Aslak, in 1841. I don't think this is the right person. Do you have any suggestions? Also, is the farm Tvitækken still in exsistence. Thanks for any imput you might have. Ann