Intenta usar whereBetween
Espero que esto funcione:
$max_scores_table= DB::table('scores_table')
->select(DB::raw('MAX(score) FROM scores_table as MaxScore'))
->whereBetween('id', array(3,5))
->where('score', 'MaxScore')
->get();
O:
$max_scores_table= DB::table('scores_table')
->whereBetween('id', array(3,5))
->max('score')
->get();