Product Catalog Images Blurry

My product catalog photos are blurry, and I cannot seem to fix it. I have gone back and forth for over a month with my theme support, and all they have told me is to upload higher res photos, which my photos are already 300dpi. Thumbnail and single product photos are fine but for some reason the category images are not. I’ve inspected elements and have changed / regenerated thumbnails but nothing seems to work.
Here is my website under temp domain:
https://biz197.inmotionhosting.com/~thewan19/