I haven't heard of one person in the past 2-3 years who is on iS and got accepted when they applied to Getty, but I've seen many people who were rejected.
(It could be that those who are accepted are sworn to secrecy, but people would find out, eventually!)
Note that even as a indie all of your images are available to a proportion of Getty buyers. Exclusives also have all their editorial files nd a selection of 'selected' files mirrored on Getty, though the former go under the very offputting category title of 'creative unreleased'. These have a Getty watermark and can sell for peanuts, but there can be occasional very pleasant surprises.