If I am not mistaken, modern printings of Latin are quite diverse in their capitalization rules (likely matches or is similar to the rules of the publishers native language). This would largely be due to the fact that upper and lower case versions of letters in the Classical period where not distinguished (of course I could be mistaken).
I am sure some people would argue one method over another (such as matching with modern Romance languages). It may just be a simple oversight by the course contributors, or this is intentional (I am sure one of them could give a better answer).
You are not mistaken: mixed-case writing started developing after the Carolingian Renaissance of the early 9th Century, and was probably fully developed by the advent of printing in the mid-15th. Of course, Latin was an important language throughout this period, but the Classical Romans used unicase letters.
Regarding the capitalisation standards in the course, I am not a contributor, but I would expect there are none. Each one capitalises as they prefer.