Update: Per Northrop Grumman, this is debris from an "acoustic blanket". Possible that it came from inside the fairing, where it would have been used to shield Cygnus from noise & vibrations during launch. Probably got snagged on the array when the fairing separated.
Here's a look inside the Antares fairing that protects Cygnus during launch, complete with mylar blankets. This could be the material that became jammed in the array. Image credit: @ken_kremer
Crewmembers observed the J-SSOD-23 deployed satellites. J-SSOD-23 CubeSat deployment mission launched to the ISS aboard the NG-18 Cargo Vehicle. The CubeSats planned deployables are: PearlAfricaSat-1 (1U), Science, Technology, and Innovation Office of the President (Uganda); TAKA (2U) Kyushu Institute of Technology (Japan); ZIMSAT-1 (1U), Zimbabwe National Geospatial and Space Agency (ZINGSA) (Zimbabwe); SpaceTuna1 (1U), Service provider: Mitsui Bussan Aerospace Inc. (Japan).https://blogs.nasa.gov/stationreport/2022/12/02/iss-daily-summary-report-12-02-2022/
[email protected]'s Cygnus space freighter leaves the station at 7:20am ET on Friday live on @NASA TV. It delivered 8,200 pounds of cargo on Nov. 9, 2022. More... https://go.nasa.gov/3NbEaJl