Anthony,
I am sure I can get conifers, such as junipers to achieve dormancy in the refrigerator, it is perhaps just more complicated, since evergreens need a bit of light, even when dormant. I have read conflicting reports about this though. It may very well be that, below a certain temperature (likely some temperature below freezing) even conifers do not need light.
I will have to try what you suggested. I am also eager to see what happens with my hemlock and spruce. The reason I am optimistic so far is, in previous experiments, the spruce I was working with (several including Norway, Black Hills and Red Spruce) already showed signs of decline at this stage whereas the two conifers mentioned above still look perfectly healthy. My Ephedra sinica (Ma Huang) is basically a foot tall
evergreen bush I sprouted from seed in Feb. 2010 and has now spent 6 full winter seasons in the fridge.
Fortunately, my Juniper is a "procumbens nana" that does perfectly in Central FL without a need for artificially provided dormancy. You might try this variety Anthony without the fridge, since it clearly has little need for chill hours. Also, FL red maple would be a good variety of Acer rubrum for you to try, since it has a very low chill hour requirement.
In summation, with my experience using this method on conifers so far, I am virtually certain I could make it work if I had the walk-in refrigerator and then installed adequate lighting for the conifers as well. As I lack the resources for this kind of setup, I will have to wait until I select the correct Powerball numbers, then I will get back to everyone.
What I will start doing is documenting my success in such a way that in a few years I can prove that this method works and for which species. I will also carefully document how I (usually in November) simply defoliate a tree, then put it in the refrigerator, without needing to worry about gradually inducing dormancy or anything like that. In my experience, it is all the same to the trees. For a dormant deciduous tree in a pot, 36F is 36F and it makes no difference as far as accumulating chill hours is concerned whether the tree is in a manmade "cold box" or outside under the bench.
Don't forget to keep trees in the fridge watered sufficiently. As with the experiences above, I have lost trees to drying out in the fridge. This might be the largest pitfall to this practice since it can be easy to forget to water in this situation at times. I have also lost trees to drying out outside, so this is simply a basic care issue.
Sorry about the upside down photo above, I kept trying to edit and could not seem to correct this.