Where can you take courses from study.com that are not longer accepted for CS major?

[LevelUP]

Where else can you do C191 Operating Systems now that the study.com equivalent course is no longer accepted? I think previously you could do a Linux course from study.com and that came in as C191 when you transferred to WGU. What are some similar places where you can do this courses and transfer it in? The advantage with doing it at places like this is that you can do it multiple times if you need to and you know eventually you'll get it done, but there's a good chance you'll get it done in the first try. It eliminates the worry for those of us prone to worry. Thanks.

The previous course you could do for operating systems was SDC Computer Science 106: Introduction to Linux though discontinued that course. 

Let me know if you find something and I'll update the degree plan.