So Hunt For Ziro was Sing's last appearance? Will have to check it out. I remember she made a comeback in Assassin. I think Cad Bane's must have been the final part of the Obi Wan "undercover" arc.
"Assassin" was Sing's last appearance. Zero hired her to kill Padmé, but after she was captured by Padmé and Ahsoka, she ended up in prison. "Hunt for Ziro" was a Cad Bane episode.