Advice on Baby mama - does this make sense? LONG

My boyfriend and I have been together for a year and a few months and are now expecting our own baby together. He has a son from a previous relationship who is two and a half.

Since his ex found out we were together it’s been hard to say the least. It started with last December her saying that he could not have their son on his own time because of Covid. I’m not sure why he listened to her but he did, so from December - April he didn’t have his son on his own. He would go see him but she would say he could only do so from the door with a mask on. So he would speak to his son from the door as much as he could (his son was only a year and a half at the time so obviously wasn’t very interested) . Then in April my boyfriend saw her brother post pictures of them all at an amusement park. Obviously he was angry, because his ex had been using Covid as an excuse for him not to have his son but she was taking their son out to amusement parks. So he messaged her saying he knew they were all going out and it was unfair. She agreed he could have his son on his own time but first he’d have to get more used to him. Fair enough whatever. So he would go visit his son and play with him about 1-2x a week for a couple hours at his sons grandmas house since his ex lives their with her parents and sisters. This lasted until July. Then my boyfriend told her it was enough time for him to get used to him and would be taking him on his own. She agreed to three days out of the week but only for an hour starting from the time their son got in his car! She said it was until he was used to being on his own with him. So Last month my boyfriend asked for more time because 1 hour wasn’t enough to do anything with him on his own. He’d barely make it home when it was time to return him. His ex always just says no because according to her an hour is more than enough. Then about three weeks ago she starts saying he can’t have him anymore until a vaccine comes out for kids his age 🙄 my boyfriend let her know he wasn’t going to let her use Covid as an excuse again. But she still started canceling on him with excuses like she was busy or wasn’t home. Then last week she said he would not be able to have him anymore on his own, because their son doesn’t like coming with him. His son always has fun with us in the little time we have him. He never cries and we always try to make the most out of the visits. She said he was more than welcome to go visit him at her house but couldn’t have him on his own. It makes no sense to me. And my boyfriend doesn’t want to have to go see him at her house. He doesn’t like being there or having to be around her just to see his son. I agree too. But all she says is that if he wanted to see his son he would. Does it make sense to you guys? Before anyone asks he does pay her child support. $500 a month and everything is recorded. He also pays all medical bills and provides his sons insurance as well since his ex is unemployed

He’s called different lawyers but none will speak to him about the case until he puts down a retainer and the cheapest we found was $5000 for the retainer and $500 an hour after that. We just don’t have that right now. We’re working on saving but until then we don’t know what to do. Does this make sense to anyone ?