Is this CPS worker doing this wrong?

The points that are questionable are numbered.
My ex wife came to me asking for help. She was on heroin and her boyfriend was abusing her in front of my son. I took her in and she left 4 days later with my son.
I told her if she left I would not let her see our son and get custody. So when she left I called cps and told them she was bringing my son to drug houses and leaving him with her unfit great grandparents. And also living with her boyfriend who got her on heroin and just got out if prison for selling and larceny.
CPS worker was a b** to me and disnt take me serious. #1) Said she couldn't take my son from her but if she was going to take him then she would take him from both of us and not just her.
#2) She kept saying I should "just go get him and that I had just as much right to him as she did" I said I cant walk in the house and get him since there is no custody agreement. She just kept repeaying herself. She was suggesting just walking in the house and grab him. I told her that is crazy and I can't do that.
I ended up getting him back by paying my ex money. And caseworker still hadn't done anything with the case, hadn't even contacted my ex. So i got with her supervisor and she made her "start the investigation"... this made caseworker very mad. She finally requested the recordings i had.
10 days later my ex was balling and begging for my son. I agreed she have him for 6 days because CPS was involved and I figured they would not let her do anything bad. Also I don't want to keep him from her because it hurts him.
#3) Now the caseworker suggested to my wife that she keep him because I told the caseworker I'd keep him if I got him back... because she continued to leave him with the grandparents and living with the boyfriend.
Can she tell my ex what I've said and suggest she keep him. Especially with PROOF she was on heroin.
She has had him 2 weeks now. And caseworker isn't answering. And my ex only let him call 2 times. I tried to get him on Xmas when she left him at her great grandparents. But when I came to thr door the grandpa threatened to shoot me and yelled like maniac.... RIGHT IN FRONT OF MY SON!!!
All my statements are true, do not imply or suggest that I am twisting or leaving anything out on purpose. I am a good dad in a bad situation.