We told the kids that SS16 isn't coming back. We told him that BM kept a secret from DH and SS16 for all these years, and the secret was that DH was never supposed to be SS16's Dad, he has a bio dad out there somewhere. 

We only told the oldest 3, as the younger 2 wouldn't understand. DD5 seemed indifferent. She said she will miss SS16 but he already left so what's the big deal. DD9 said she almost felt relieved because she had been hoping SS16 was going to come back this whole time and she had such anxiety over the whole ordeal. She is relieved to not have that on her heart anymore. That sent DH into tears, it's so hard knowing her little heart was weighed down so much. DS6 was the worst. He cried for hours. He's now the only boy in the family and he always loved having a big brother. He still cries whenever SS16 is brought up, we try to ease his pain. We said maybe one day he'll realize the family he has here, but we don't want them holding out too much hope so we keep it very wishful. 
The order came back today. It's already been sent out to BM, MEO, and Vital Statistics to get DH's name off the birth certificate. 
DH and I are getting married this summer. He said he'll use the money from MEO to pay for our honeymoon. 
I'm not certain how MEO will collect that money but I would suggest that they will have to start collecting it from BM. She said in court that she doesn't receive a monthly payment, but DH's credit goes down by his support amount each month so...? Anyway, not my problem. 
I am so grateful for this group. Although I guess I am no longer technically a Step Parent, you guys are the only ones who understand this plight.