Not sure about the blue marlin losing its tail but the did a bunch of checking to make sure it qualified under their rules.
As far as the white marlin getting disqualified, from what I have read, apparently no one is allowed to handle the rod once the hook is set except for the angler who is competing and apparently the first mate at some point assisted the angler somehow and touched the rod. I guess this all came out during the polygraph test they are required to take

If it looks good, you'll see it
If it sounds good, you'll hear it
If it's marketed right, you'll buy it
But...If it's real, you'll feel it
Kid Rock