In Oklahoma if the court order states certain things the police can be called and the non cooperative parent has no say.
For instance, my daughter and her ex had an agreement that S was to be picked up by one parent at 6 pm on Sunday and stay until the next Sunday until 6pm when he would be picked up by the other parent. They were allowed to go and see the child any time they wanted during the others week can you see the stupidity of that judge????
Every time he came to see S during her week she tried to make it enjoyable and not stressful. When she wanted to see s during his week he would start fights with her to get her arrested for trespassing. I would take out the court orders and tell the police she had the right to be there but since it was not specified in the order as to what they had to do they would make her leave.
If he has a court order stating he has visitation at a certain time until another certain time then the law is on his side. She cannot refuse to let him have the child even if the child is sick and puking.
But in any case he needs to get this agreement amended to give him the whole weekend. It is obviously too stressful for her to be switching back and forth so much. He also needs visitation on holidays for extended periods.
My friend has a brother who is in the military. He is stationed in Oklahoma and was happily married, or so he thought. His wife went home for the Holidays with their infant and never came back. She was only in another state but still it was several states away. He got visitation right away where he got the child over Easter for several days and then he got several weeks in the summer too. It just doesn't have to bee every other weekend.
They might use an intermediate person who is neutral to take the child from her then wait for him and give him the child. They could be called to testify as to the behaviors of the child when she sees him, sees mom, etc...also if the child was dirty, clothed properly, etc...if accusations were made. It could be to his benefit or not.