I don't believe that the PRO document is relevant. There are other things that might have led you to the second repository. For example, a friend might have spotted the name and brought it to your attention. I think the extent to which you publish the data you found is simply a matter of your personal judgement and sense of good taste. Others have provided some examples. I did a bit of uncharged work for someone which was only intended to whet his appetite for the hobby. As it happened, I found evidence that clearly proved my friend's illegitimacy. I didn't report it to him. I simply claimed that I'd failed to find marriage information. So he can smile at my incompetence and I haven't caused him any unnecessary pain. Much better for him to find out for himself if he wants to.