the ACF wysiwyg field is using the built in editor in WordPress so it should be possible. However I think this falls more on the HTML Editor Syntax Highlighter author. I’m guessing he/she targets only the regular editor specifically and would have to add in the ability to target ACF editors as well.
I had to hack my own solution to get the syntax highlighting to show up for the wysiwyg editor. It would be nice if it was built in. Simply insert this code in your functions.php file to get code mirrors’ syntax highlighting: