I would venture that somewhere between 2009 and today you took a long break from the game. Why you took a leave and why you returned might help you to determine why you want to play WGT.
For some of us it is the challenge, much like real golf. For others it is a social experience; again like real golf. And for still others it is the competition. For most it is some combination of these elements.
Why do YOU play? You need to answer this question in order to decide how to proceed. Everyone here can give you all kinds of advice, but that advice is always based on their own reasons for playing.
Your original question was about going back to a lower tier. There are at least two work arounds that you can use. Neither will put you in the Tour Master tier, but each will allow you to play lower tier games.
The first is to play practice rounds. You set up the conditions including the tee box location and the green speed. These rounds will not be recorded and will not count toward your average but they will count toward consecutive day bonus as well as raising your level.
The second option would be to join a country club. But this option requires that you pick a club that has some club tournaments that do NOT use default tees or greens. (Sometimes these are called "red tee" tournaments but can be set with any tee box or green speed.)
You also have the option of starting your own country club and then setting your own tournaments. You could set up a tournament using Wolf Creek back 9 with Master tier greens and tee box. Any country club tournament will count toward average as well as level and consecutive day bonus.
Other options going forward will most likely require some level of time or monetary commitment in order to make equipment upgrades. Watching 75 videos every day to get 150 free credits is the easiest if you have a smart phone and the WGT app. No smart phone means using an emulator such as Nox or BlueStacks with the WGT app to watch the videos. (It is possible to use all 3 of these at the same time to speed things up.) Purchasing credits is also an option.
Whatever you decide, playing the game is about YOUR enjoyment. If it is not fun, don't do it.