Calling MD after final round to amend the situation?

Here is the deal,

I have been on a structured products interview from an top bank. The bank used two different head-hunters, call A and B. I got throught round 1, round2 and went on the final round. The structured product consist of Sales, Trading and Structuring and was looking for 2 candidates.

Round 1: I got contacted by head hunter A, telling me to meet one MD, responsible for Sales. I got a decent and quite awkward interview experience, feeling he didnt like me very much. Somehow i got through.

Round 2: I got contacted by head hunter A, telling me to meet head and VP of the structuring desk. Better experience. Before the interview, i was told by head hunter A that I was being considered for this desk, so I thought these were the people that were going to decide my future.

Round3: having been with head hunter A all the time, now head hunter B called me and said head of trading and the entire capital market wanted to meet me. Having checked his background, I am quite certain this one has the most decision power of all the people I have met. During the interview, he asked me what I want to do, trading, sales or structuring. Having been told by head hunter A that I was going to be placed in structuring, I answered structuring, of which I thought was the safest answer.

some days later, head hunter A called me saying the head of trading is being on vacation, the bank will decide next week. I got to know that only 2 candidates went through round 2 for the final round. 3 days later before "next week", worried about the process and I wanted to know more about how it went for the second candidate, I called head hunter A. She told me he is put through to round 4 (HR and contract writing). I asked which desk, she told me trading. She also told me that they need to wait til next week to give me a final answer. Now I called head hunter B, who told me that the bank decided not to take anyone because they couldn't find any suitable candidate.

So clearly, the bank tells different things to A and B.

Anyway, I don't see myself getting the job, mostly due to that I didn't tell the trading head I wanted to do trading. However I do want to do trading, but thought they were looking for people filling up structuring desk. Is there anything I can do right now? The final round went very well (Except the what you want to do question) and the only reason for they to reject me is due to my lack of interest in trading, I guess. Would it be a good idea to call the head himself next week and be honest about what I want to do? Or should I just move on to other applications because calling him wouldn't change anything?