Select the link to "Share: Copy Link". There is no need to add the proxy prepend to the Swank URLs. So the URL retrieved from "Share: Copy Link" is what you would post in your syllabi or course/LMS.
There is a referrer that the vendor placed in the background so the URL will automatically direct your students to the USD login.
https://digitalcampus.swankmp.net/usd500716/watch/6C46A9B4B0230805?referrer=direct