I agree with most of what you wrote here, but the article discusses two separate labs, one of which was looted and is now missing some radioactive material.

There’s not much detail as to specific materials and quantities, and it seems like the other lab that’s no longer being monitored has more dangerous materials. But still, they are saying that the looted material could be used to build a dirty bomb, so it’s not clear to me that the headline is just pure hyperbole. My guess is the calibration standards and waste that is mentioned as missing are not enough to make a meaningfully dirty bomb, but I don’t really know