As expected.
The one behind these disappearance cases was most likely Orochimaru.
Given Orochimaru's personal strength and methods, it was nearly impossible for him to leave any traces at the scene. In the original work, he probably only exposed himself later because he could no longer restrain himself—or perhaps did so deliberately. As his capture and slaughter of fellow shinobi from his own village became more frequent and the numbers rose, it became easy for him to let something slip.
No one could guarantee they would perform the same task with peak concentration and perfect execution every single time. Orochimaru was human too, and no exception. Of course, it was also possible that the personal forces and bases he had established abroad had already begun to take shape, and he felt it was time to leave the village, which was why he became so unscrupulous. Orochimaru had clearly underestimated his aged teacher's strength while overestimating his own.
If Sarutobi Hiruzen had not hesitated in the original work and ultimately been unable to bring himself to strike at the disciple he had once valued most, then Hiruzen—who still retained around seventy percent of his prime strength at this point—would have had a very good chance of killing Orochimaru on the spot.
Fate truly toyed with people.
Shōji had yet to decide whether Orochimaru's affair would benefit or harm the Uchiha Clan. For now, he could only follow the orders from above and conduct the investigation.
A search mission.
In any case, they were merely going through the motions. It did not matter whether they found any clues.
What mattered most was what role he himself should play in this incident.
*Still, there is no harm in gathering firsthand information first. As for what to do afterward, that can wait. Watching from