Bob Kirkland is not Red John. This is about Homeland Security, and Kirkland is the HS agent on the show. As we know, however, there is more to Kirkland's involvement in Lorelie's case than merely Homeland Security issues, but we're not sure yet what those his motives are.
Why is Homeland security involved in the case of Lorelie? I believe it is because some of the Red John cases -- here comes my conjecture -- involve human trafficking, which is an international crime that is frequently connected with other international crimes, of interest to Homeland Security. There are two reasons I think this is the case.
1) In the Red Letter episode, the victim, Hector Brava, was killed just before he was about to give a speech where he was about to expose a human rights institution for their involvement in human trafficking. Apparently, Brava's being blackmailed and subsequently murdered had nothing to do with his speech, but that is questionable, since his murderer stole the notes to that speech. They conclude that Bigalow stole the notes to make it look like that was the motive, where as the motive of the killing was quite convoluted. Could it be that he claimed his motive for blackmail was money rather than expose his involvement in a much greater crime. And if this theory works out, a crime that ultimately traces back to Red John. I'd lie about it too if that were the case.
Incidentally, Kristina Fry plays a major role in that episode. If she were somehow also involved, it also implicate Stiles, who just happened to know Kristina's whereabouts after she had been allegedly kidnapped. There is nothing saying that Frye was involved in the case she was called in to help solve, but since she already is a questionable character, her involvement in solving crimes has to be questioned. This was in fact, the first case on the show where her collaboration was requested, even though it was her second appearance.
2) Kidnapping is frequently a part of RJ's MO. I can think of three cases that occur in the following episodes: Red John's Footsteps, Red Sails in the Sun Set, and Red John's Rules. In Red Sails in the Sunset, the kidnapping in question occurred much earlier, but it is in that episode where we learn of Miranda Martin's disappearance; in Red John's Rules (Lorelei appears again in a video) the kidnapped victim is a baby. In two of the three cases, the kidnap victims are intended to be Red John "gifts" -- the are not vendetta or ransom kidnappings.
We still do not know about the motive of Miranda Martin's kidnapping. We Just know that it was facilitated by an agency that was supposed to care for vulnerable women; and subsequently that Miranda ended up dead. We also know that Kirkland was obsessed with the Lorelei case. His involvement could have something to do with her sister's case also. We just don't know what his personal interest with the Martins's is, yet it is the only RJ case where Kirkland/Homeland Security takes interest.
My guess is that HS has one set of reasons for pursuing RJ with regard to Lorelei, while Kirkland has a much deeper ulterior motive, a personal motive related to the deaths of Lorelei and her sister.