Question

The words: wanna and gonna would be changed to want to, going to in a clean verbatim file

Answer 1

Yeah, it's true.
A Clean Verbatim file is a transcription which contains the verbatim transcript of an audio file. It does not contain any filler words.
Truncations of single words like ‘wanna’ and ‘gonna’ will be corrected to their proper spellings of ‘ want to’ and ‘going to’ respectively.

Hope it helps u:)

Answer 2

The words will change as a clean verbatim file can't contain any filtered word or words in their short form. The Verbatim file only contains Verbatim script.