You can go about this two ways. List everything you are thinking of, and you will get a response saying whether you qualify for them, or what you need to get them. You’ll get 90 days to remedy them. The down side of this approach is that it may not be fast or easy to amend your application to drop the things you cannot get right away, and until you do, your MMC is delayed.
You can also be realistic and leave out the stuff you cannot do in the next 90 days. That probably includes leaving out QMED. That takes 6 months of experience, and unless you have time that can be counted in the military or on vessels that didn’t require you to have an MMC, you are not going to get that in 90 days. The advantage is that as soon as you are found qualified, you’ll get the MMC issued.
I am not sure where you get the costs for QMED. You don’t need a course for those endorsements. The courses are to substitute for taking an exam from the Coast Guard. You can study on your own and just pay a fee of $140.00. Those courses might be approved for some part of the 6 months required for QMED, but it won’t be for more than 90 days so you are still going to need to get some time on your own.
Also, for courses that have been approved to substitute for taking an exam from the Coast Guard, they are valid for one year. Don’t take the course until you are certain you will meet all the other requirements within a year of taking the course.
Take a look at NVIC 07-14 for Rating Forming Part of an Engineering Watch. You are probably going to need that at some time in your plans. Make copies of Enclosures 2 and 3 and take them with you when getting the sea time. When you are ready, have the Chief Engineer, or 1st or 2nd Assistant Engineers do the assessment and sign you off. If possible, do these before December 21, 2021, after that date the engineers will need special approval from the Coast Guard to sign. Until then they don’t.