URL found in home page not found by BSR

Hi. @ https://www.insightdesign.com.au we have several images that live on https://staging.insightdesign.com.au.

If I perform a Better Search Replace, looking to replace https://staging.insightdesign.com.au with https://www.insightdesign.com.au nothing is found in the wp_posts table.

Can you help me determine why please?

Thanks,
Steve