The chain of events could have been:
1. Blue Toad either gets hacked, or gives their data to the FBI or someone else.
2. Somehow this data ends up on an FBI agent's laptop.
3. Anonymous breaches the laptop and gets the data.
4. Anonymous sees all the UDIDs and mistakenly thinks, "Apple and the FBI must be in cahoots!", and publishes it.
1. Anon breaches laptop, finds UDIDs.
2. Anon tells other anons he got the UDIDs from a laptop.
3. Other anons tell more anons it was a government laptop.
4. Release group writes "FBI laptop" in their pastebin.
(5. ??? --> 6. Profit!)
The heterogeneity and disorder in Anonymous (at least it was like this back in the day) means that the chain from leaker to releaser -- usually passing through several people and IRC channels -- plays out a bit like a game of telephone. This serves to protect the leakers, but it can mess with some of the details.
Details like that don't emerge over the course of a game of telephone. If this story is correct, and the data was not in the possession of the FBI, someone deliberately decided to make up an elaborate lie.
It's entirely plausible that someone, disliking the FBI, made up an elaborate lie to discredit them.
See how ridiculous you sound?
During the second week of March 2012, a Dell Vostro notebook, used by Supervisor Special Agent Christopher K. Stangl from FBI Regional Cyber Action Team and New York FBI Office Evidence Response Team was breached using the AtomicReferenceArray vulnerability on Java, during the shell session some files were downloaded from his Desktop folder
From here http://pastebin.com/nfVT7b0Z
I don't think it is helpful to make excuses for Anonymous. If you'll allow me to abuse the ethical alignment terms: They appear to be a chaotic neutral, not a chaotic good. I'm not sure it makes much difference if they lied or are incompetent. Especially since there really isn't a specific 'they'.