Hello again and thanks for the information.
Firstly, it's a really good sign that the children were returned to you and that social services have closed their file.
Your husband is very unlikely to get legal aid for his application to court. Legal aid is now only available this type of application for victims of domestic abuse but ONLY if they can provide the very detailed and specific evidence that the Legal Aid Agency require. From what you say, it's is unlikely that your husband can provide this evidence.
I can see you must be under an enormous strain at the moment, but it's most important that you do not give him any chance of making any further allegations against you - so make sure you remain polite to him at all times, whatever the provocation from him. Please also make sure that you scrupously comply with the court order for contact between the children and him, again to aoid the risk that he makes any further allegations agaiinst you.
Let the children see Cafcass without you in the room, so that there can be no suspicion from anyone that you tried to influence the childrne in any way.
With regard to your legal costs, I can hear your frustration, but unfortunately, it is extremely rare for the court to make a costs order in a family case - altough you can of course ask the court to do so. However, even if you did get get a costs order in your favour, from past history, it seems that your husband would ignore it anyway, so you would have to go back to court to enforce the order.
With regard to his non-payment of child support, you need to chase up the CSA/CMS about that - but unfortunately, they are notoriously slow in dealign with their cases.
Some face-to-face legal advice - both with this case, and if you are now thinking of starting divorce proceedings - would probably help - here's where to find a specialist family law solicitor:
I hope this helps and I wish you the best of luck.
Thanks and best wishes...