Thanks for your interest. I posted this to the ThemeForest dashboard -I do not know of anyone using Extinct with Woocommerce but will be happy to know if someone is doing so.
Having experience with integrating one of my earlier themes Enigmatic with WooCommerce, I can say that Extinct should work with WooCommerce since they share the underlying framework. At least if there are issues, if any, I should be able to help.