Experienced caretakers who have done long meditation retreats are very important.
While they have no contact with a meditator, they are the lifeline if a meditator needs help. The meditator leaves a note briefly explaining their needs and on pre-scheduled days, the caretaker drops stuff off at given drop points for the meditator to retrieve later.
It’s also common for experienced caretakers familiar with retreat teachings and guidelines to ignore certain impulsive requests from retreatants that wouldn’t be beneficial for meditation.