They found the image and they ran with it. They didn't contact Declan or the BBC. And today, they're both apologising.
As it happens, I was at university with Declan - we worked on Imperial College's student newspaper Felix together. I'd seen the photo before - when he posted it to Facebook, sharing a joke he'd written himself. Yup, the caption was by him - and was the best part of a year old:
click on the comments link to see the discussion
And there we have it. Two media outlets turned their journalistic instincts off when presented with something fun on social media, and made fools of themselves.
You don't get to stop applying the basic techniques of journalism just because you found something on social media. Verify, check, double-source. Or you'll be apologising to your readers - or your editor - pretty quickly.