It's what is called a "hobby case", meaning that the Bureau really only wants you working on it on your free time. Larry only studied the case when he went home. He said he'd just take copies of the documents home with him to read at night or weekends. Of course, sometimes you'd work the case during "work hours", but they really preferred you not to do that. I think that is what got Larry in trouble with his bosses. By going to the media about it, it brought in more leads which meant A) Seattle Office had to answer more calls from people, and 2) that Larry would have to spend more actual "company time" working the case.
Larry didn't throw the current guy under the bus on the interview, but privately he said he doubts the current case agent has done any substantial work at all on this case. He said he'd be surprised if the current agent has even bothered to spend any time at all on the Gryder chute since it was retrieved last year. Current case agent apparently has a large sized role in something involving Asian gangs in Seattle.