Force Theme to use WooCommerce Image Settings?

My site has 22,000+ images. The theme (FlexiShop2 WC by PrimaThemes) forces me to use “regenerate thumbnails” every time I have new images, and that means running it from start to finish on 22k images, or sifting manually through 22k images under Media to regen just those that I need.
This is prohibitive and I’ve had one host shut me down when regen thumbnails ran for 5+ hours trying to get them all done and almost destoyed the servers CPU. (for reference, site is styleinvyte.com)

On the other hand, I have another theme (not preferable for presentation purposes) which simply shows the images fine every time. It obviously pulls in the images according to the core Woocommerce settings/code, not its own which would then reguire the regen…Also, Jetpack Photon works fine with this other theme, which can save page load time, while my PrimaThemes theme ignores Photon settings.

Can someone please offer insight on how to modify my child theme to just pull images in this manner (from Woocommerce core) and thus circumvent the whole “regenerate thumbnails” routine?

I did inquire with Primathemes about a month ago (and followed up) and never got a single reply.