OK, I think I may have this figured out after seeing the application. First, it is Company D, the Sumter Guards. I saw he was wounded at the Wilderness on May 5th, 1864. The first application looks rejected and then possibly the last one is accepted. I was looking only in the "J's" for a Jenson, Janson, Johnson, etc. At any rate, I went through the entire roster of Co. D and found the man I think it is. The Compiled Service Records listed him as Frank Tanzas. Company clerks were notorious for poor spelling sometimes but when you consider that many of this company were of foreign birth, there is no telling how Mr. Janssens was pronouncing his name when put on the muster rolls. I feel fairly certain that this is the individual and I will correct his name spelling for my records. Thanks for bringing this out. Here is the information that I had on him from his CSR:

Tanzas, Frank, Private

Frank Tanzas was a single laborer in New Orleans in 1861. He was a 19-year-old German immigrant when he chose to join on June 19th, 1861 at Camp Moore. Frank was present at all actions up to being wounded at the Wilderness on May 5th, 1864. He was absent, wounded until Cedar Creek and was then present up until he shows on a list of refugees and deserters received from Fort Monroe on April 8th, 1865. He was taken to Washington D. C., where he took the Oath and was released. Frank was furnished transportation to Philadelphia, PA. His name is also listed under Tanses.