Who decides the final ballot text when the initiative is put to a vote?

National Election Office (website)

http://valasztas.hu/en/ovi/219/219_1.html

II. The submission of the proposed national referendum question

The proposed referendum question should be submitted for verification to the National Election Commission on the sample of the form for the collection of supporting statements prior to the collection. There should be only one question on the form for the collection of supporting statements.

http://valasztas.hu/en/ovi/219/219_3.html

The judgement of the initiative

The National Election Commission decides on the verification of the question or on its rejection within 30 days after it has been submitted.