In my country, if you do this kind of thing without proper backing, you will be questioned seriously for not minding your business and spreading misinformation
There is a chance he happened to stumble on the fact OGNasty changed his passport by pure coincidence or chance.
It is public information, after all, anyone can have access to it. Even I have spent some idle time checking some prominent profiles on BPIP, like satoshi's and those that are most recognized around here, it is a matter of curiosity on statistics.
So in that aspect, we do not have further proof this person is actually stalking or following OGNasty's stepf on the forum.
It makes sense we are supposed to expect someone creating an alternative account to ask for help.
However, I personally think that it is also good for the community if we pay attention to things we could consider to be anomalous. For example, if someone noticed that a high ranking and recognized member changed their password, and email, it would be okey to point it out, because an account like that could be used to scam people for a significant amount of money if ended up being stolen and the rightful owner did not realize it on time.