Boston This (adoption) is so much not an easy or ideal situation ever. And I can see it gets people very upset, so I am very wary of debating it with you.
But OK, I am happy to discuss this and happy to learn something from you but only if you are not going to get angry with me for holding different views.
Maybe I have always felt slightly different about birth verses adopted families, long before we actually adopted, three years ago, the idea of adoption had been on my radar, possibly for the last 25 years, maybe it has coloured my view of birth verses adopted families.
My first experience of relinquished children was an orphanage where some kids had parents but did not live with them, it was back in the 80s/90s when people could volunteer in Romanian orphanages.
Anyway, I am trying to explain where my own thinking comes from, I am not trying to convince you of anything.
"I find it totally wrong that a BM relinquishing her baby should be allowed not to give any info about the BF."
To start with in an ideal world a mother would never feel she had to relinquish her baby, so we are already starting from a difficult situation.
I'd hope if a relative of mine were attempting to relinquish a baby they may consider me or other family members, as i do feel children can do very well with relatives, if they are capable of care for the child.
I think I might actually get through the screening process but still end up not necessarily being the best choice for a baby/child.
So there are all kinds of conflicting things here right at the start, about duty, and expectations etc.
The statement you made "I find it totally wrong that a BM...." comes from a situation where, yes, ideally babies would only be conceived where their arrival was welcomed (not necessarily planned but wanted) and all well .
But here we are relying on the birth mum being willing to talk and being able to tell the truth and then telling the truth.
I can think of so many situations where a birth mum may not be able to name the baby's father, so what should be done then?
Or where doing so could put her at risk.
"If the SW says no we never bothered" well I would be very shocked if a social worker said that, but i can imagine a situation where a social worker might say the information from the birth mum was so patchy we cannot identify who he is.
So here is the problem as I see it. You seem to agree that "If like you say there are extenuating circumstances - DV, rape etc, danger to the BM or child, then of course the judge will accept that, but otherwise the SW must show that all BM and BF have been sought."
What is to stop any birth mum who does not want her child going to wider family or birth father or birth father's family from saying just that.
I am not defending anyone lying about the risks but I am saying how would anyone know?
"In terms of statistics I do not know if they even exist, but it is widely accepted that children do better if they are kept within their Bfamily if at all possible."
There are loads of views that have been widely accepted for a long time about who can do what and what is of value. I would rather see evidence.
Of course all things being equal it is true that the best place for kids is with birth parents and this is only challenged when something goes wrong. That's what I mean about this not being an easy or ideal situation ever.
"When children are taken into care SW will always look at the wider family, is there a possibility of kinship care - BP are asked is there anybody you would like to put forward to be assessed?"
The reason they are taken into care is because the parent/s has/have proved themselves not able to care for the child or there is suspicion that they may not be able to do so.
But a relinquishing mum has not been found unable to care for her child or even suspected of it.
You do not need to say because I do understand about confidentiality etc but is the baby in your family already with adoptive parents?
Because my comments up thread were about that scenario, where a baby had been placed, because we were discussing this in relation to the OP and her situation.
I am sorry your relative has had to go through this and it must have been very difficult indeed. I am not anti-men by any means and I know a lot of wonderful fathers, including my own dh.
I am also sorry your child/ren feel the loss of their birth family
and hope you will find all the things you need in this matter. Our own son has not been with us anywhere near as long as your adopted child/ren and maybe this is something we will encounter too. 
For our son he was not relinquished and was not able to stay with birth family. If it had not been us, it would have been someone else unconnected to him, I know that much.
Again, you do not need to say but do you know why she did not want him to be accessed, could she maybe have been genuinely confused about who father way?
"BM has no say now." Could birth mother not choose to withdraw the choice to relinquish the baby now? I am not sure how long these things are allowed to be left but I know of three adopted babies who were relinquished prior to adoption. One, the birth parent/s never contested, one birth mum changed her mind and one where another situation happened.
In all cases the babies were with adopted families when things happened (if they did) - if you see what I mean.
"It is very close to the bone for me at the moment also."
I know and I really do not intend to upset you.
You are making me worried my views are very abnormal! Maybe I should confess neither of my children are very easy to parent but *strangely) the adopted one is actually a lot less hassle (at the moment) than the birth child.
I try to imagine if it matters to me that he is adopted, and it just doesn't. I try to imagine how it feels for him. And all I can go on is what he says and how he displays, of course I do not ask him outright, just want it to be an open possibility to talk about such things.
I think it does matter a little because he never wants to talk about birth family! We try, we don't want him to forget. He came to just at an age where it would be possible for him to have forgotten his life before (on the surface) and we know that to do so would be very bad for him long-term.
Maybe I am just odd, I find my fertility/adoption journey has made me question almost everything about how babies come into families and perhaps I am still trying to work it out!
But for our son I just want to do our best
as we are not his last choice or worst choice, we are now his best and only option.
Feel free to PM me if you wish to. I am very aware this is a public forum!