Secure Checkout works with logged in users, but not with Guests

I’m having a problem with Guest Checkouts. We have “Force Secure Checkout” enabled, and our Checkout page loads fine when someone is logged in.

When a Guest tries to go to Checkout, loading the page times out with “too many redirects”.

Disabling all plugins besides WooCommerce doesn’t help.

When I turn on wp_debug, I get this when trying to load the page:

Notice: wpdb::escape is deprecated since version 3.6! Use wpdb::prepare() or esc_sql() instead. in /home/joinclub/public_html/wp-includes/functions.php on line 3573

Here’s output from the “Debug wp_redirect” plugin: https://pastebin.com/AhhfeK8W

Here’s my System Status: https://pastebin.com/RdcrKdmS

Here’s the link to the page: https://www.joinclubm.com/checkout/

I’ve googled around, and will continue to do so, but can anyone suggest a way to troubleshoot this?

https://www.ads-software.com/plugins/woocommerce/