Benning's brigade fought George Estep's Eighth Indiana battery on the 19th of September around the Viniard farm, and again on the 20th, this time near the Poe House. I believe all eight pieces that Benning captured on the 20th belonged to Estep.
I believe that I have accounts of Benning's men capturing at least one flag from the battery as well. I'll try and verify this and come up with biblio info sometime in the next few days
best,
Andrew Johnson