Why wasn't Elizabeth surprised when Wild Fang appeared in Time Crisis 4? Because he's the apprentice of Wild Dog, the guy who's been known to come back from the dead without fail. It isn't much of a stretch that his apprentice would have a similar habit.
Something bothered me about Wild Dog's portrayal in the fifth game. Instead of being a serious, downright intimidating boss, here he's hamming it up big time, his fighting style has completely changed (using mechs and vehicles instead of fighting the players directly) and even giving a cheesy line right before detonating himself. Even his famous leitmotif is missing. Then it hit me. Wild Dog's entire job in this game was to play "keep away" with the briefcase, not to mention one of the people chasing him is his own boss! He knows full well he doesn't need to take this seriously, and he's not! He doesn't need to win, he knows he won't get captured (since he could blow the lid on Robert any time he wanted) and if he gets beaten, he's one detonation away from getting away. That's also why his leitmotif is missing from his fights. It was never a real Wild Dog fight. It was him screwing around with the VSSE and having fun with it.
Becomes even more brilliant when you remember what Wild Dog's last action in the game. Launch the briefcase all the way to Robert's base. While this may seem like a massive oversight on Wild Dog's part, remember that Robert was one of the VSSE agents that beat him in the past. He knew that by launching the case there, the VSSE would find Robert's base and, as per norm, screw up Robert's plans and most likely kill him. Though he did it in an indirect fashion, Wild Dog got his revenge on one of his past foes after all.
Actually, he didn't launch it all the way to Robert's base. He launched it off and it landed in a jungle somewhere. Keith found it, picked it up, and brought it to Robert's base. Which raises the question: How did Keith know the traitor would have a base somewhere nearby?
This feels like Keith was the one who hired Wild Dog and is very happy about the situation where two of his past enemies are fighting each other. Keith at this point is suspected of being hunted down and hiring Wild Dog is a complete left field for the VSSE.
As we see that Robert's base is located in the jungle, the case most likely landed nearby, allowing Robert's men to retrieve it. Keith most likely followed their trail back to the base.
In the fifth game, you're initially led to believe that the traitor to VSSE is Keith Martin, but it's actually Robert Baxter. In a meta-sense, the fridge brilliance is that in the second game where Keith and Robert first appeared, Keith was the "Player 1" character, so if you didn't have a second player, Keith was the "default hero". So of course in the fifth game, Keith is actually a hero here as well.
