Perhaps you're misreading it...
'He then went out on his bike while cycling at high speed past Ellie another cyclist kicked out at her and knocked her off her bike'. I think you have interpreted it 'past Ellie, another cyclist..', ie there was a third cyclist that kicked out, but it would make sense if Ellie was just another cyclist and so Aaron did the damage. Therefore it would be UAM with the defence of intoxication.
What exam board and year is this scenario from?