Missing overimage.png

I’m getting a 404 on the below image on my homepage.
https://chicagobourbon.org/img/overimage.png

The page source shows:

<link rel='stylesheet' id='themes-wplp-masonry-css'  href='https://chicagobourbon.org/wp-content/plugins/wp-latest-posts-addon/themes/masonry/style.css' type='text/css' media='all' />
<style id='themes-wplp-masonry-inline-css' type='text/css'>
.wpcufpn_widget_masonry .wpcufpn_listposts li .img_cropper:before{background: url("img/overimage.png") center center no-repeat rgba(231,149,0,0.7);}.wpcufpn_widget_masonry .read-more{border-top:1px solid rgba(231,149,0,0.7);}.wpcufpn_widget_masonry .wpcufpn_listposts li{width: 45%;}@media screen and (max-width: 640px) {.wpcufpn_widget_masonry .wpcufpn_listposts li {width: 45% !important;}}
</style>

There is a file named overimage.png in the theme directory:
wp-latest-posts-addon\wp-latest-posts-addon\themes\masonry\img

Is this a bug in the plugin?