Update and advice please

[KBDad]

For those of you that read my previous post involving my 3 year old son. Here is an update. Me and my ex wife are going into mediation once again on October 19th. Here is what is going on now. I still have not received the paperwork involving my son from the daycare center she is taking him to on her week. Im supposed to be able to get his toddlergrams and sign in/ sign out sheets on who is picking him up and dropping him off. I went in to the daycare 3 times to try to get them. Now my lawyer is working on them. My ex's lawyer sent me a letter stating that I was harrasing the daycare and disrupting Scott's daycare, and that I wasnt calling the number I was supposed to to get ahold of him. I was calling the house where he was residing she wanted me to call her cell phone which my lawyer just told me to do and not fight her right now with it. But as far as daycare I only saw him once where I had a 5 minute conversation with him with the teacher's permission and the second time he spotted me when I was leaving. My ex's little brother went to the daycare my son is at and therefore they know her family and are making things difficult for me. Also her lawyer takes her kids there. I have started videotaping all drop offs and pickups done between the two of us to keep her civil during those times. She isnt acting up on tape but atleast she isnt belittling me or swearing during the drop offs anymore. When our son is at my house for about the past month my son doesnt want to speak with his mother. He either says he doesnt want to talk to her or he covers his ears. I have been trying to coax him but to no avail. Now yesterday when I called to speak to our son the first time she said to our son "do you want to talk to daddy or do you want to play". Which do you think he choosed? He chose to play. So I said I would call back later. I called back and she asked him if he wanted to talk to me. He said "no" and then started to cry in the background. Anytime my son has ever not wanted to talk to someone on the phone. He always said "he didnt want to talk". He has never just said "no" which makes me very suspicious to the aspect that she is trying to get me back. It is illegal to tape phone conversations in PA it is a felony. I checked it out. So I can't tape conversations. Well I could but that would just give my ex more ammunition. She has been in and out of my son's life for 3 years. And now that I am finally divorcing her she now wants custody of our son. Even when she was around she never took care of him it was always me who fed and changed him, me who played with him. But the problem is proving any of this. He also actually has his maternal bond with my mother I dont know if that is something that may help me. I am requesting at the next mediation for a custody evaluation and a psychological evaluation done but how do I make sure that I get a custody evaluator that is fair. Im not asking for a CE that will side with me but I want someone who can see through the show she puts on and truly does what is best for my son. I took my son to a psychologist who I found out before I left that she also does CEs but I know my ex will not go for it nor should this psychologist necessarily do it because it may look like she would be partial to me. I guess my biggest question is as a father fighting for what is best for my son, what should I go into this mediation with? My ex doesnt answer my phone calls all the time when I call and doesnt return phone calls. WHich is breaking the court order. My son is in daycare till between 3-5 pm M-F when she has him when she is off on Mondays and the rest of the week she gets off at 1. Im not going to agree to anything if the court order can't be enforced which the only thing I can do is get her for contempt but I need proof that she is doing these things and without illegally taping her I can't get.  So my question basically is simple. Any advice anyone can give about things that I should bring up at mediation or things I should go in there prepared with would be greatly appreciated. I know that father's especially need to be more prepared so any advice would be greatly appreciated.
KBDad in PA

[smtotwo]

Why not send her a letter stating that ALL calls to and from your home are now being recorded.  If she disagrees then she must now communicate in writing only, except for calls you make or she makes to you to speak to your son?