Not if they knew how to handle it safely. However, if some idiot did so on the spur of the moment, perhaps.
I'm going to be really interested to know how it supposedly fell off a truck, given the regulations for radioactive devices. The devices I am familiar with were much less radioactive than the ones in the OP and had to be stored in a sizable lead container.
I can see the item falling off a truck due to incompetence, but surely it had to be in a lead container, so why was it not in one?
BTW, if it was stored in a lead container it would not have been found by the radiation.