the way I remember the show was that Dan originally told Lois that he was DEA, but eventually we found out that he was really FDA.
Vicki, just to clarify what happened in the episode, Dan really was DEA. His cover story was that he was a corrupt FDA agent, willing to accept a bribe to grant approval for a dangerous drug. When Bobby told Lois that he was FDA, not DEA, he was reporting the cover story that had been "leaked" to the streets. In other words, Bobby got it wrong.
Kathy