Tuna is cheap, they wouldn’t risk not using it just for having to deal with headlines like this. I believe this says more to the accuracy of the testing than it ever does about the product myself. Disgruntled employees would love to hurt subway if they knew this and left the business, Subway isn’t stupid and knows it’s not worth it.
I remember once that McDonald’s was accused of using ground up earthworms in its hamburgers by some conspiracy nuts to cut corners and used as a filler.
McDonald’s kinda squashed that one pretty fast by pointing out that a 1k lbs of earthworms cost a lot more than 1k lbs of beef, plus the specialized equipment to process it. Story disappeared almost overnight once they showed that it would cost them more than not using it. Subway will be the same way, this story was put out for headline eye grabbing results and click bait more than anything else.
“Accuracy of the testing...”
Sometimes I’ve wondered about that but it could be like voting-whoever interprets the results kind of thing.