Based on the re-run rotation for the show, the episode with Deniro (and the Muppets) will be the next filler episode for the regular time slot (11:30 Saturday nights on NBC) when there is no new episode (most likely will Feb 12, 19, or 26), check local listings. (this week is a repeat of Collin Farrell, and the next week they are back live with a new episode), but next time they repeat an episode to fill the time slot it should be the Muppet.
NBC always ends up showing the new episodes of the current episode twice (origianal "live" airing, and a repeat of it on a week with no new episdoe) during the regular show season, (and then repeated again during the summer months), then E! gets the episodes for repeating the next year. So the episode will be coming up soon.