Thanks for this.
make sure to save the theme options to flush the generated code was the part I was missing. Thanks for reminding me of that. I got lines lines 411 and 412 looking like this
$custom_styles .= 'input[type=submit], button[type=submit], input[type="file"], .wpcf7 input.wpcf7-submit[type=submit], .gform_wrapper input[type="submit"] {background: ' . $accent_color . ';color: ' . $accent_alt_color . ';}';
$custom_styles .= 'input[type=submit]:hover, button[type=submit]:hover, .wpcf7 input.wpcf7-submit[type=submit]:hover, .gform_wrapper input[type=submit]:hover, .mymail-form input[type=submit]:hover, .gform_wrapper input[type="submit"]:hover {background: ' . $
but I had forgotten that step.
You can mark this as resolved.