Done. If anyone wants to do the same you just need to replace line 169 WKO_ignoreAnswer(); with the following lines. This does, however, rely on having the SRS Indicator script installed to detect whether it’s a burn review. (actually, all it does is disable the hotkey, if it really was just a typo you can use your mouse and click the footer button)
if (!$('.progress-burned').length) {
WKO_ignoreAnswer();
} else alert("You can't ignore burn items.");