Need Advice, Accused but innocent!

Hi i'm desperate for answers our lives have been turned upside down because of this.

My Daughters father (My ex) was accused of sexual abuse by my Daughters friend, My daughter and her friend are both 9 years old. How it happened was my daughter was having a sleep over for her birthday, she had 2 friends sleep over at her dads that night as she was with him that weekend. A few months pass and before he knows it his at home alone and police come to the door, his arrested and charged with sexual abuse. They take computes and usb drives, the mattress the kids were sleeping on that night and his mobile phones. He was taken into a cell at the police station and had the hearing or whatever, remanded as they had lack of evidence. So they sent him to prison to await the next hearing. After about a week they have the hearing, and the prosecution were so cruel, pretty much stating that he was guilty and he should stay in prison till the next hearing also it was said that he couldnt see his daughter at all and after hearing that he broke down and started crying telling the judge that he didnt do it and he is innocent. The judge sent him home on Home detention. Where he is now. When they released him they just pretty much chucked him out on the street with nowhere to go, I had to travel hours to pick him up and take him back home. As soon as he was back at home he had to ring the police to tell them that he was home and to fit the ankle band tracker thing on him. And because the police have taken the computers his had a horrible time getting anything sorted, so I have helped him with money, shopping, food, setting up accounts and accessing any phone numbers, he couldn't even ring his family to tell them anything as he didn't remember the phone numbers because they took his phone so his borrowing one of mine.

The thing about all of this is I believe 100% that he is innocent, the 2 girls that were at the party the same time this other girl accused him, both have said that nothing like that happened and they told the police that.. They have no evidence against him. They will find no evidence as nothing what this girl is saying is true.. The worst part in all of this is that they have said he cannot have ANY contact with his daughter.. None not even indirect contact, no Christmas presents not even telling me to tell her he loves her, absolutely nothing...

My concerns are.
#1 Are they allowed to treat him this way when he is still innocent?

#2 Even without evidence could they still convict him?

#3 Will they just drop the charges if no evidence is found?

#4 if found to be false allegations will they get in trouble? Or could he sue them?

$5 Maybe this little girl is being abuse by someone else and is blaming him to protect the real person doing it? Will they investigate that?

Im really worried about him and even tho his my ex I still care about him, he doesn't deserve this neither does my daughter, he is not like that never has been never will be im absolutely sure about that, i will give my life promising that he is innocent.

So please help I have been loosing sleep big time over this, its not right that this could all happen over one false accusation. Its so wrong...... Thank you for reading .