Looking at the HTML for one of your images:
<img class="aligncenter wp-image-8666 size-full owl-lazy" data-src="https://bradleyputters.com/wp-content/uploads/2018/12/44867B9F-E9AF-4B19-A651-928211C6DE6D.jpeg" alt="" width="1270" height="1270" src="https://bradleyputters.com/wp-content/uploads/2018/12/44867B9F-E9AF-4B19-A651-928211C6DE6D.jpeg" style="opacity: 1;">
Note the ‘aligncenter‘. When you insert images in WordPress you are given the option on how you would like to align the images. In Visual Edit if you go now and click on the image and ‘edit’, a popup screen will open. Under DISPLAY SETTINGS there will be an ‘Align’ option. Select ‘Centre’.
I had already done that, and just reconfirmed. When I made the images now 517×517, it left-aligned them again.
Try adding the following CSS:
#slider_8664 .owl-item .sa_hover_container img {
display:block !important;
}
No luck. Also, when I preview the slider, it shows the images left justified as well. But in the visual editor, it shows them centered.