Hi Tina,
A friend of mine is involved with writing a new unit history of the 15th Indiana Infantry and would love to get a picture of this flag as well as your ancestor's story for it.
I can also suggest a good appraiser for you. He does charge a fee, as do all appraisers. He has extensive experience with Civil War flags.
Please email me at Biggsk@aol.com
Greg Biggs