Of course, you have done the right thing with the cage. But you want to know how to give the little baby the best chance to thrive now that the gophers have done their dirty deed. In the video I provide a link to, I would use the meals they talk about. Bone meal, fishmeal, fish emulsion, kelp meal, seaweed meal are all recommended. I have used Jobe's fruit sticks for three years and with the exception of one year? I have had good crops. If you transplanted the peach, reducing water loss is important. I have heard that liquid vitamin B-1 is good for preventing transplant shock but I have never used it. You can find it at the nursery or garden center in bottles.
Since the lady in the video is speaking about dealing with the dwarf in the desert, and you live at a bit of a higher altitude, I am not sure you need to dig down as much? I don't have a gopher problem in Superior so I need to look on the web for advice. Best of luck, and congratulations on the fruit you have gathered. My full-sized peach tree has given me a good harvest this year of about 59 peaches and I am enjoying one as I type.