Repeat based on OP clarification
Since you do not know which fields we will associate in the executor table (img01, img02, img03), I would suggest creating a view that improves the layout of the executor table so that we can reference it. Here is the code I would use:
SELECT id, Name, Img01 AS Img, Img_Txt01 AS Img_Txt
FROM artist
UNION ALL
SELECT id, Name, Img02, Img_Txt02
FROM artist
UNION ALL
SELECT id, Name, Img03, Img_Txt03
FROM artist
, . ( Img4, Img5 ..). :
SELECT event.*, images.Img_Txt
FROM event
INNER JOIN
(SELECT id, Name, Img01 AS Img, Img_Txt01 AS Img_Txt
FROM artist
UNION ALL
SELECT id, Name, Img02, Img_Txt02
FROM artist
UNION ALL
SELECT id, Name, Img03, Img_Txt03
FROM artist) AS images
ON event.idArtist = images.id AND event.Img = images.Img_Txt