At the end of The Walking Dead Season 7 Episode 14, Sasha and Rosita's tenuous partnership came to an abrupt end. Sasha decided to save Rosita's life by locking her outside of the Sanctuary's gates while she ran inside to take on the challenge of killing Negan all by herself, though there was no guarantee that Sasha would live through the attempt. She decided it wasn't Rosita's time yet, choosing to potentially sacrifice herself instead. While fleeing from the building, Rosita caught a glimpse of someone mysterious in the dark outside of the Sanctuary. But who did Rosita see on The Walking Dead?
The person was little more than a silhouette with long hair holding a crossbow, which led many fans to assume it was Daryl. However, that doesn't seem to be the most plausible answer, though the episode didn't actually reveal who the person was. Daryl was all the way in Hilltop and unless he hopped in a car immediately after the Saviors left with the doctor (which he did not appear to do), then there was no way he could have gotten to the Sanctuary that fast. Instead, it seemed to be more likely that the person Rosita saw was actually Dwight.
There have been plenty of parallels between Dwight and Daryl all season long, with Dwight adopting Daryl's signature aesthetic by stealing his jacket, motorbike, and crossbow. Sherry even drew direct comparisons between the two in her goodbye letter to Dwight. So while those surface similarities could make it easy to mistake one for the other in the dark, it made more sense for Dwight to be lurking in the shadows of the Sanctuary. He is a Savior, after all.
Dwight running into Rosita could have interesting consequences as well. Every since returning to the Sanctuary after his initial escape (taking Sherry and her sister in tow), Dwight had been struggling to tow the line and obey Negan without question. He followed the rules, but it was clear he was chafing under them and Sherry's final flight from the Saviors (and over onto her own show on E!) seemed like it might push him over the edge. If he was finally ready to turn against Negan, then meeting with Rosita could result in the formation of an alliance between the two.
Dwight did join up with the Kingdom and Alexandria to fight Negan in the comics, acting as a double agent within the Sanctuary walls. The show might be setting that up by having him meet Rosita, which would be a different way of accomplishing the same goal. If it was Dwight who Rosita saw, then the Alexandrians might end up with a new ally on their hands.