A recital is a performance given by one person, whereas concert can be given by one player or a groups of players. When there is one main player suppported by someone else, such as a violinist accompanied by a pianist, this is usually called a violine recital.

As far as I know, a concert is usually called a recital when there is only one pianist playing. But it is not wrong to say it is a concert. As a matter of translation, I would leave it as "concert" in your case because リサイタル is often used in Japanese and the author somehow chose to use コンサート