Taking courses at WGU not part of my degree program? And credit by examination

[sciencemathematics1]

I was looking to get a math major for TESU by taking these courses.
Now, I am thinking that I could just take them with TESU instead, as I am a new jersey resident. I need to choose between starting at TESU with math or starting at WGU with computer science. I want to have more time to study the CS material before enrolling with WGU because if I do, I can go theough their competency based program faster.
I don't necessarily need these math courses or major for my CS path, but I would think that a math major would go well with CS in general and can be incorporated with it, especially when working in more advanced fields of CS. I may even consider mathematics graduate school.
I'm also considering getting a bachelors or a master in data analytics from WGU after my CS degree because of data analytic'a applicability and its relevance to the study of AI/machine learning.