worried

I'm not sure on where I should share this but I'm in need of some advice. 
My fiancé has a court order for contact with his daughter. She is 3 and there have been ongoing concerns. 
I am not slating her mother in any way as I know how hard being a parent can be but I'm not sure on where to go from here. 
My partners child has a strong odour when she comes (of wee) we soon found out that she doesn't wipe when she uses the toilet. I understand children may need assistance here and there but in my opinion she should be independent. She says that her nan wipes her bum but it isn't the first time her knickers have been ruined. She is unable to take clothes off (I understand that kids  learn at different paces but she shows no signs of independence) 
Her hair is always knotted and we have had to get it cut without permission since it is always in her eyes
The clothes that she is sent in are 18-24 months which I know could be tolerated if they still fit in looks but they don't.
There is a communication book in place as her mother refuses to speak to my partner and there has been at least 5 occasions where we have mentioned the child's personal hygiene and we only have her once a fortnight so it goes to show that it's an ongoing issue 
Again, I'm not slating we are just concerned since her basic needs are not being met. It isn't fair that she has to sit in dirty pants because the importance of person hygiene isn't being reinforced when she's at home with her mother 
We have spoke to child protection and obviously it isn't immediate danger so they've said to keep doing what we're doing by writing in the communication book but that's being ignored
If we were to take it to court how do we provide evidence?