meaningless, all three. If they were mishandling Po-210, then how come that out of all 6 [??] "no-goodniks" only one got it hard and fast - where are all the others, in what hospitals? To handle Po-210 and not get hurt in the process takes training, special equipment and concentrated effort. Here one has a professional assassination job, with the means chosen for the difficulty of tracing [how long did it take them to find out?]. The same means, once identified, drastically narrows the culprits circle.
Did you read post #48?