theme options: list all categories, post and custom

Hi, is there a way to add custom taxonomy to the drop down menus of the theme-option panel?

On my site I have “post” type and “events” type.
I have “post” taxonomy and “events” taxonomy.
I’d like to display events of a certain taxonomy on the featured section of the homepage but inside the theme options panel I can choose only from post taxonomy.

I have a child theme but I dont’t know how to overwrite function render() inside field_cats_select.php to pass all my taxonomy to the get_categories($args).

Thanks