While I like that he managed to get them together, and hopefully helped them sort out their problems, I DO have to admit that going to the same house twice in that situation rubs me a bit the wrong way in terms of taking advantage of a situation... Then again, that was a different time, and I'm not about to say he was wrong, it's just not something I felt comfortable doing.
It happened to me once, though in reverse.. Wife called for a rekey of the place saying only that her ex husband still had a key.. All her ID was in place and even had a utility bill in her name alone, so no problem.
The next day the husband called for the same address and explained that he KNEW she'd had the locks rekeyed, and they'd just become separated but hadn't filed any paperwork and that she didn't have a legal right to lock him out. I apologized, explained to him that I'd actually done the job for her and that there was nothing I could do, as anyone who's name is on the house has a right to change the locks until there's legal paperwork in place preventing them from doing so, so he had legal right to enter and rekey again, but that I didn't feel it would be ethical for me to have any more involvement... as to do so would be taking advantage of their situation. (I mean think about it, that could have continued several more times... not to mention potentially putting me in the middle of their marital issues, where I decidedly do NOT want to be)
I referred him to another qualified legitimate locksmith in the area who did the job. Neither of them ever called either one of us again, (or any other locksmith in the area we know) and neither of us were ever contacted by any lawyers, so I don't know what happened to them after...
In THAT situation, though, IMO, as long as you're practicing due diligence, following the law, and handling it as professionally as you can, there's really no "right" or "wrong" way to handle that one... you just have to do what you feel is right.
I DO want to say that when I rekeyed the house for the wife, she didn't show any signs of abuse, physical or otherwise, and unfortunately I DO see it often enough to recognize it... Had I even suspected any sort of domestic violence, I wouldn't have been so quick to even give him that much help.