How to view iPhone logs (work with sim, traffic) (not jail, under warranty)?

Question

iPhone

iPhone 4S, under warranty (yes, there was a warranty replacement almost a year ago and the warranty is still there).
The owner of a working phone (and a working SIM card), already being in international roaming, took out a SIM card for 4 days, replacing it with a local one. One day, when, according to her, the SIM card in the phone was local, in an instant there was access to the Internet in the amount of more than 4,000 rubles. Neither before nor after there is even minimal access to the Internet. Only one day in roaming. There is no reason not to trust her when debriefing. The question is, how can I get access to the logs of an unrooted iPhone 4S to confirm her words that the sim was removed at that time and inserted at that time. I have no doubt that such logs are kept by the phone. The question is how to get them.
If there is no way to get such logs, is it possible to find out which applications and when made access to the Internet?
The question is not only that there is an understandable reluctance to pay the operator for a service that she did not use, but the question is how to understand what happened to the office phone. A kind of easy forensic, but still with a bias not towards forensics, but towards showing the operator a log on the phone, what and when was done. If for me, as for the IT department of a mobile services consumer company, the log is read-only, it will be even better - I cannot fake it and it should be the basis for a decision in our favor.
PS: because my opsos receives data on expenses in multi-roaming after the fact (and even with a delay at times) from local operators, it is not at all a fact that this is my operator "evil and insidious", so I would not like to name names;)

Answer 1

Some logs are available from the iBackupBot program.
Whether there is what you need - I don't know.