What's on the last picture is mostly casing. They seem to have found a magnetic roll that hopefully contains data, but there's some risk they found nothing
It looks to be from a VHS tape. Also, a Cockpit Voice Recorder (CVR)/Flight Data Recorder (FDR) would likely be setup to record in a loop. You can do that with magnetic tape, but not in the configure it appears to be in.
I'll try to remember to look up what CVR would have been used for that plane when I get back to work in a week.
