You don't say which part of the world you are located, but it is apparently in a cold part (USDA Zone 5) of the northern hemisphere. The short answer is yes only if the garage will stay cold but not freeze. The plant was grown in a greenhouse, so even though it is from hardy stock, it is not hardy now. Azaleas need gradual cold and shorter days to harden off, so this plant is still tender.

It would be best to let it go dormant in a cool place with low light. The back of a garage away from the outside doors could be ideal if the garage is attached so that it won't go below freezing. They may need to put up some plastic to protect it from the cold air when the garage doors are open. Then, in the spring after your last frost, it can go outside. Many hardy azaleas are not hardy in USDA Zone 5, especially when young. When they are about 3 years old they reach full hardiness. Do you know the variety?

Your friend needs to guard against it drying out. An attached garage can be a low humidity environment. The ground should remain moist but not wet. It will need good drainage. Make sure drain holes are open and unobstructed. It might be good to repot it into a larger pot with a layer of gravel in the bottom to assure good drainage.

Here is a link that might be useful: How to grow azaleas and their problems.

I truly appreciate your input! If I have any other questions - I'll be sure to ask. Thank You - I'll give it a shot!