Hi there! There are several services who need persistent storage, check here for an overview diagram.
If I'm not mistaken, there's the fileserver, elastic, mongo and redis. All info is scattered over these (e.g. model files on fileserver, logs on elastic) so there is no one server holding everything.
I'm not a k8s expert, but I think that even a dynamic PVC should not delete itself. Just to be sure though, you can indeed check by making several PVCs and each assigning them to the right service using the chart values .
Hope that helps!