The departure story had been assembled from four systems and one assumption.
A booking platform said the hotel account was settled. A travel spreadsheet said an airport transfer had been requested. A transport company recorded a vehicle assigned to that request, then reassigned it. A visitor database displayed the return of a numbered badge as an exit time.
Someone had placed the four lines in chronological order and called the result an itinerary.
Wanjiru sent the corrected analysis to An with a warning that it was not proof of deliberate deception. Records could be wrong, copied, or misunderstood without anyone setting out to fabricate an alibi.
“Then why did everybody repeat it?” Yanchuan asked.
“Because it came from another office,” An said. “No one checked what that office actually knew.”
The inspection of the service compound’s document office had found a printed copy of the contractor’s travel summary in a folder labeled staff departure. The summary gave Yansheng an apparent sequence of checkout, van transfer, and departure from the service area. It cited account references but no direct witness.
The folder had been made after the missing-person report. Its label was administrative, not evidence that the traveller had left.
Yanchuan recognized the shape of the error from his work. A dashboard imported a field from a supplier. A manager copied the dashboard into a presentation. A client cited the presentation. By the time someone asked about the original sensor, the number appeared to have several independent sources.
He asked Mei to look at the chain.
“This isn’t four confirmations,” she said. “It’s one story passed through four formats.”
“Did someone make it on purpose?”
“I can’t tell. The same propagation can happen when everybody is in a hurry.”
He wanted a person to blame. An had asked Luo to correct the wording months earlier. Luo had done so in later communications, but the older summary remained in circulation. It was easy to imagine malice in that persistence.
The documentary dates pointed to something less satisfying. The first spreadsheet had been prepared to reconcile expenses. A manager had copied its descriptions into a staff-welfare update. The update had then been attached to a case inquiry without the original limitations.
No one had documented a direct sighting at the claimed departure points.
Yanchuan called Luo with the revised chain beside him.
“Can you tell us who described this as a confirmed departure?” he asked.
Luo said he would find the earliest message carrying that wording. This time he did not ask the family to stop troubling people.
The answer arrived three days later. The wording had first appeared in an internal note by a coordinator who summarized the partner’s expenses. Luo had repeated it. The coordinator’s source was the invoice spreadsheet. There was no evidence in the records provided that the coordinator had personally seen Yansheng or checked the transport change.
Luo acknowledged the error in writing. The firm would send a correction to the contacts to whom it had supplied the earlier version.
An read the letter twice.
“Will he apologize?” Yanchuan asked.
“He has corrected a claim. That’s the part we needed first.”
She put the letter in the correspondence folder and added a note to check whether the official case contact received it.
At work, the Guo study produced a smaller version of the same problem. A marketing team had prepared a one-page summary describing the pilot installation as capable of meeting peak demand. It had taken a conditional result from the technical appendix and omitted the summer-temperature assumption.
Chen returned the page with tracked changes. The marketing manager argued that a caveat would make the product hard to sell.
“Then sell what you’ve measured,” Chen said.
Guo joined the call and asked to see both versions. He did not insist on the more flattering page. Instead he asked how many potential customers would accept a performance range instead of a guarantee.
Yanchuan said he did not know. The question belonged to the customers, not the model.
Guo looked disappointed. Yanchuan decided he could live with that.
In Kenya, the case team checked the visitor badge allocation against shift reconciliation. The records showed that one badge had been returned in a bundle, but the desk had not logged which staff member collected it from the visitor. The electronic exit time had been generated automatically at the end of the day.
It was a precise time attached to a movement nobody had witnessed.
Wanjiru added the finding to the departure corrections, making three unsupported claims the family could now identify with their original sources. A fourth claim—the unverified messages from Yansheng’s account—remained separate. Those messages asserted safety and privacy, but the sender’s identity had not been established.
“Don’t call it an alibi,” she told Yanchuan when he used the word.
“Why not?”
“An alibi is a claim relevant to a person’s whereabouts. This is a constructed itinerary that has been used to explain an absence. We don’t know who, if anyone, intended it to protect.”
He changed his summary heading to Administrative departure narrative.
The new phrase was dull enough to be accurate.
That evening An’s son asked why adults sometimes knew exactly when his school bus departed but not when his father was coming home. An told him a timetable described what a bus was supposed to do; it did not tell them what had happened to Baba.
The boy considered that and moved his toy bus across the bridge.
“I’ll count this one myself,” he said.
Later Yanchuan stood beside An at the kitchen counter, drying the dishes while she washed. They had done the same thing on the night of the first uncertain messages. The phones lay within reach, but neither of them checked one when it lit with an ordinary notification.
The corrected documents had taken away an easy explanation. They had not supplied a harder one.
Yanchuan filed the letter from Luo and closed the spreadsheet. A machine could arrange honest entries into a persuasive story. When that story became someone’s account of a missing man, the error could outlive every individual who had made it.
He wrote one more question for Wanjiru: Was there an individual who actually saw the visitor leave? He resisted adding what he thought the answer would be.