The files should be in a folder labeled BPAV, and that folder should reside inside another folder. If that’s the case, you’ll need the Sony XDCAM Transfer software to convert the files for FCP use. If it’s not in that configuration, you’ll need to have your client re-submit it exactly the way it comes off the cards, or, better yet, as Quicktime EX clips that have been processed by the Transfer software.