iflg. Gyldendals røde

Merriam Webster:
cache: to put (something of future use or value) in a safe or secret place <an eccentric who cached money in odd places, such as under the boards of the floor>

This is not one that needs translation, because it is a loan word from English.
Caching in computer does indeed mean saving data, but there is a difference between saving data on a hard disk, saving data in cache, and buffering data.
In this case, cache is the correct term, because the contract implies the data will be deleted in the future, even if the index is kept.