Child support in Nc

So.....my SO has been paying child support to his ex for almost a year since he's moved out of her house and they split up last year. He has one kid. She has two. He Is a father figure to both kids. Her son is not his biological child, but he raised him from a baby so he is close to the child. All year long, since he left, he's paid her every month. 300.00 cash. 250.00 on her car payment each month and 77.00 a month for a bed he purchased from Kimbrells so they had some where to sleep bc she had bedbugs and the kids couldn't sleep on the other ones. So he bought a expensive bed for them. The car and bed won't be paid off till April and June of 2017. He still pays, has receipts...etc. well, she also calls him and tells him she has no money for food. He is not going to let them go without. He goes and gets food and brings it. She won't let him take the kids over here to stay. At one point she has told him not to see the kids and still pay her child support. His rights have not been taken away. They have court soon bc she went to DSS and lied about getting child support. He has her on voice recordings and receipts for the car payments he makes and bed payment each month since they split last year. On top of that she wrote on the papers that he gives her nothing. Lol he's paid her and her bills every month! She told him he's not the father of her son, bc he really isn't but he's been taking care of him anyways...just to read the court papers and see her asking for her son to be included in the child support payments. I don't know what the judge will say to this? She's denied him and only wants money. Plus, the whole year I have tried being respectful as I'm a mother too(2 boys and his unborn daughter), I have let him go see the kids at her house without complaint until now. In a few months I will give birth to his other child. I want my family together. I feel I gave her time to sort things out with him and don't want him spending half his time there bc she thinks she has to watch him like a baby around his own kids. He's such a good daddy to the kids. As mean as she is...he's tried respecting her. I think she needs a reality check. He's been so nice, paid everything and done extra... just to have her lie to DSS and act like he hasn't done anything. Makes me angry. Does anyone know how to determine in NC how much child support she will get? He's paying alot already. She lied said she hasn't been working and she has had two jobs this past year, Got food stamps..etc....lied to him and keeps the kids away unless it's visits to her house. Idk what to think.... need some advice. Dss called him (I already reported him living with me) and ask if he lived there with her. He said no, bc he hasn't. They stopped giving her food stamps and told her stop lieing (that's what she told him...) (dss did call for a verify though) I don't know what's going on exactly ..she must of screwed up. Plus, when they go to court the court papers have it as she received nothing all year.. it's notarized by dss....😹 Boom she lied.....now what when he shows the judge the proof of all he's done....plus she's had a few jobs...she lied on paper about that too... What do ya"ll think the judge will do. He makes 17.00 a hour some weeks he works 8 hours. Some he works 25-35 ....depends on if they have work. He's an iron worker it varies bc they go place to place and if it rains alot or not. His check is never consistent. What should we expect?