Pretty annoying that they're going down this route. Explains why only Bertram and Smith are set to appear in the next 2 episodes though. McAllister must have been the man who was shot, Haffner and Stiles are eliminated because they didn't have the offending tattoo. 

Of the 2, my guess is Bertram. We've seen Smith commit crimes onscreen, we've started to learn a lot about him. Bertram is still a mystery though, interestingly he is yet to display any signs of a phobia, so maybe that'll appear next episode? Bertram is more sophisticated than Smith, he seems a man who would appreciate some decent piano playing. Though again the question remains. Why was Smith giving orders to Bertram, and if Bertram is RJ, why didn't he just kill Smith for disrespecting him? RJ has killed for less. 

Basically the writers have turned this into an almighty clusterfuck, the clues are making it harder to solve, rather than easier, and are leaving poor suspects as the only suspects.