I am glad I found him yes, and if I explained the whole story of how I found him and met him, well if I didn't find him the year that I did then I may never have found him because it was the only year his phone number was in the phone book.
I never had any high hopes about meeting him, knowing the men my mother has been with and the things my mother has involved herself in I wasn't exactly expecting anything high quality.
It was never really a big deal for me, it wasn't something I pined over for years. There was just the occasional curiosity that never got truthfully answered. I'm not really any better or worse off knowing him.

I can understand your niece's cycle of wanting to see him then wanting nothing to do with him, it is the same with my father. I sometimes want to see him, but then I get hurt and vow he can go to hell for all I care. But then it will eventually wear off.
I think if she wants to meet him only she will know herself whether or not that is what she needs. There does become this need to know who this person is, just for closure at the least. My father, well my life was bad enough growing up without him as it was. But I do have the closure that I do know him now. I do think sometimes bad things happen for good reasons, and my mother not telling him I existed meant I didn't have to grow up with him. But even then, it has been very tough. I mean, my mother bought drugs from him last time we went there (she's decided to become completely clean now so I know it won't happen again, but seeing your parents buy and sell drugs from each other is not something anyone needs to see).

It's not that the whole thing was a shock to me, it's not like I'm dealing with anything I've never had to be exposed to before (drugs, alcohol, crime, abuse, blah, blah, blah), I think there is just some disappointment that he was just another same old same old.