Timing chain replacement is not a maintenance job so it will not show on any normal service records. Service repair histories are only kept by the individual dealer (I think).
I am not familiar with 101 service but any job operation that refered to the timing chain would begin with the group designation 05.
The important service info on your timing chain is the color of the top chain rails. The life of the chain is relatively unimportant. My recommendations are to replace the rails every 75k miles and the chain every 150k (but that is only for ultimate security as the rails are the problem). BTW the lower right rail will need to be replaced every 250k to achieve the same security (as they wear through at around 300k).
Bosch Master, ASE Master, L1
33 years MB technician