Interesting. It was in there rattling around...I'm glad it isn't some piece from the guts. Thank you!Hard to tell if it's any part of the original exhaust or not, but I can tell you the fiberglass-looking stuff in the muffler opening is not original. Maybe someone used that 'packing' stuff combined with the short piece of metal tube when they re-installed the mufflers. The original tubular silver graphite-like packing Honda used on some muffler joints isn't available anymore.
Got it. Thank you!Looks like spacer/collar used when the muffler inlet is larger than the pipe.