Interesting theory. I don't know if I buy it, but interesting.
No, I don't believe he was converted. That was never my theory. I think his son is being used as a tool to get him to do what they want. Get Henry and/or Kill Ana Lucia and we won't kill Walt. I'm not sure what I think his purpose was? I'm almost leaning towards his being sent to off AL rather than to free Henry. My main reason for not buying into the converting theory is his apology to AL prior to shooting her, I think he was sorry, and the Libby shooting seemed to take him by surprise and he seemed sorry she got mixed up in it. He didn't need to kill either woman, he could have just locked them up once he had the gun. There was a reason he shot them, I think that was his purpose.