MQ's Bachelor of Business Administration (UAC code 300203) does appear when I search for it on UAC by typing in either the name of the degree or its UAC code. When universities discontinue or temporarily cancel courses, this will be reflected on UAC and the
"This course has been cancelled" notice will be shown. However, MQ's Bachelor of Business Administration appears to still be on offer. Because of this, you may wish to contact MQ to identify and address this issue. On the other hand, UTS's Bachelor of Business Administration is only offered to Aboriginal and Torres Strait Islander people and its application process is separate from UAC, hence the reason that it does not have a UAC code.
With that being said, both MQ and UTS offer a Bachelor of Commerce and Bachelor of Business respectively, which are options that you could consider including in your UAC preferences. It is also important that you are aware of the main difference between a Bachelor of Business/Commerce and a Bachelor of Business Administration. A Bachelor of Business/Commerce provides allows you to choose one or more areas to specialise in, whereas a Bachelor of Business Administration focuses on building all-rounded knowledge of business fields in a way similar to that of an MBA. This means that it does not allow you to choose a particular major.
I hope this helps!