Ok. So I have a few apps in place that seem to be limiting/reducing the bot now. I was typically getting several abandoned carts per day and most were testing a credit card. Now I only had a couple in the last few days and none of them were able to test a credit card. The last app I put in place was BeSure Checkout Rules https://apps.shopify.com/checkout-rules. I am not connected to these guys at all, but the app seems pretty good. Here is the condition that I set.
I also currently have SecurityKing enabled to block all traffic from Brazil, since my checkouts have locale=en-br in the URL. However, I am not sure if it is effective since the bot goes directly to a checkout page and I am not sure if it triggers then.
I also have Shopify Flow (see previous posts) which deleted the customers from the bot abandoned carts.
Very much a bandaid solution. Shopify should fix this!