Danny,
I am sorry- I don’t know why I had told you to reset the roles again- you had already been advised to do that and did notify me that helped with one issue.
Ok– please try deactivating all plugins except WooCommerce and WC Vendors. This allows us to check and see if there is a plugin conflict.
Test and see if you are able to list products.
If not, would you pass along an admin password & login in a private reply- and I can take a look.