Child maintenance

[stunner1901]

My son's ex has somehow found out he has had a payrise and has gone to the csa. They have increased his payment to £332 a month, she has told them he only has daughter less than once a week but she stops most fri/sats (so she can go on drinking/coke snorting nights) plus every thursday after school fdor a few hours. If she declared this the amount would drop to £280 but now he has confronted her she is denying that she went to csa and is now saying he won't see his daughter at all.
What are his options please? is there anyway he can put the money into a joint bank account if he opens one in his daughters name with him as a co-signee?
TIA

[atticus]

I cannot help in respect of CSA/financial aspects.

In relation to contact with his daughter, your son can apply for a Child Arrangements Order under the Children Act 1989.