Woocommerce swears on the subject of Retail that it requires an update. Will you be able to give updates?
There are updates for retail-child/woocommerce/content-single-product.php version 3.4.0. Kernel version-3.6.0,
There are updates for retail-child/woocommerce/emails/admin-new-order.php version 3.5.0. Kernel version-3.7.0,
There are updates for retail-child/woocommerce/emails/customer-on-hold-order.php version 3.5.0. Kernel version-3.7.0
The Retail theme is already up-to-date with the content-single-product.php as that is the only WooCommerce template override in the theme.
Please look at the file paths where they reference retail-child. Our basic Retail Child theme does not contain any template overrides, so those files must have been added by yourself to your own child theme. You will need to update these yourself.