Which tense is correct?

Her son was in a gang before he was incarcerated. Now that he is out, his mom is scared he may/might go back to his gang.

Which one means “you never know, you might go back to them. How would you right that in one sentence? Does one of the below mean that?

You never know if he’ll go back to them.

You will never know if he goes back to them.

thanks