TMI : my brother accused of rape

about a week ago my 15 year old brother was accused of raping a girl he went on a few dates with.

backstory : my younger brother whom is in year 10 (uk) went on a few dates with a girl who is also the same age as him, they met on instagram and it seemed okay. they then decided to go on a date in which my brother came to the conclusion that he doesn’t fancy her in that way although she was clinging onto his arm, trying to kiss him and showing affection although he wasn’t really into it. he decided to go on a few more dates with her hoping perhaps he might see something in her, but he didn’t. one night she messaged him telling him to come over and her friend was with her and they could all hang out etc, like normal teenagers. be aware, this girl messaged him when she was high and drunk in the afternoon but he came quite late about 4-5 hours later. he arrived, she seemed to have calmed down with the drugs and alcohol, was back to her normal self along with her friend. they all were having fun, talking, getting to know each other etc. she asked him if they can have sex (i’m unsure if it’s her first time or not, but it definitely wasn’t my brothers first time since he had a girlfriend prior to all this). they got it on, while her friend and older sister were in the other rooms, nothing out of the ordinary. Until, my brother went home and now it was the next day, he messaged her if everything was okay and she replied “what happened last night? i don’t remember.” and he explained everything but she acted clueless to what happened.

a few months went by, they haven’t spoken in a while until she messaged him saying “give me this certain amount of money and i’ll keep my mouth shut otherwise i’m telling the police you’ve raped me.”. in shock my brother didn’t know what to do, he doesn’t work, he didn’t let me nor my parents know of the situation and just let it pass by because it didn’t think she would actually do that. until she did. my brother went to school like he normally does until he was called by his head of year into a room with a detective explaining the situation. he had to hand his phone in and everything he knew about this.

last weekend he went to his first interrogation with his solicitor and replied “no comment” to every question.

both him and the girl handed their phone in with the police however, he did not screenshot the message she sent him and he deleted that account quite a while ago.

will he be charged? as of what i know and only from his encounter he didn’t do anything wrong, he currently has a girlfriend whom he is happy with and just wants to focus on his basketball career. he doesn’t have any violent history or upbringing

any tips?