Thanks for your interest in BSSCommerce extension.
For your concern, we'd like to confirm that on default Magento 2, if guests would like to check Order info and print order, they have to redirect to Orders and returns page, then click Print.
However, on many Magento 2 sites, customization is as an obligation, the customization causes Orders and returns page path to be changed and Print button for guest checkout not working. That is why we have to disable Print button for Guest checkout.
If you'd like to us to make Print button for Guest checkout work for your site (which requires unique custom code according to your site's customization), we are willing to offer you our customization service with additional fees.
Please let us know if you have any concern.