Open/close icon settings for sub-accordions

Thanks for the great plugin. I’d like to have sub-accordions within accordions, but the open/close icons are not displaying correctly when accordions are embedded within one another. The parent accordion icon closes if a child accordion is closed, and the child accordion icons open when the parent is opened. This image gives an example: https://s21.postimg.io/in4ddwqd3/embedded_accordions.jpg

There is no issue with actual opening and closing, just with the icons. Is there any workaround? My site is still being developed, so I can’t provide the URL publicly, but I pm’d it to the author regarding a separate question. Thank you.

https://www.ads-software.com/plugins/accordion-shortcode-and-widget/