Hi Tami, the certification exam page says "It is important to note that training alone will not provide you with the knowledge and skills required to pass an exam. Successful, on-the-job-experience is critical to providing you the knowledge needed to pass the exam." Marketo University Online covers a lot of the basics, but I don't think it goes into enough detail to cover all the topics and scenarios in the exam. Even the Core Concepts 1 & 2 courses may not be sufficient.
The exam guide lists out specific areas and activities that you will want to be confident in. Reviewing the detailed Marketo documentation and getting as much hands-on experience as you can in these areas will be helpful in preparing for the exam.
The exam guide also has a link to sample questions that you can use to gauge your preparedness.
Hope this helps, and best wishes on your certification journey!