Hikergirl, and Sunshine Highway....
I don't think anyone is making any assumptions here (except by the OP) that the grandparents have been evil manipulators.
And I have to respectfully, and very strongly disagree.
Here is what the OP posted:
He's tried to contact the family through FB. They responded by deleting everything.
That seems to be a huge "Period, end of story."
Not only did this family want the legal freedom and protection of having full custody and rights, (which I could understand) they have actively tried to keep any contact or relationship at all from being established. That is all I need to know... In no way is it ever considered 'the best thing' for the child/young adult to perpetuate a huge lie and to try to control contact with a family member.
As I said earlier...
While, IMHO, this family is very very very WRONG.
Two wrongs do not make a right.
All indications seem to be that any efforts to go around this situation and sideline this kid are very sure to be met by her only known family with a lot of negativity, conflict, turmoil, pain, suffering..... I can't begin to imagine how this would ever be in any 20 year old's best interest.
The OP would like to think that her DH is just so great that this kid would be so blessed to have him in her life.
But, that is a very narcissistic and one sided viewpoint.
It could very well be a very painful curse.