You can prune them to the same shape in several years. Pruning of the longest branches actually stimulates new branches and will stimulate growth. Obviously you don't prune much off the smaller plant. You just prune the tip off the longest branch to stimulate growth of the other branches. Always prune them after the first bloom in the spring.

From the encoreazalea.com:

Encore Azaleas® require very little pruning to retain good form and do not need "dead-heading." If you think your Encore Azalea® needs pruning, do so immediately after the spring flowering for maximum bud set. Light pruning of more established plants will stimulate growth and flowering.

Well, I could prune it if it had any size to it in the first place. These azaleas are very small. I bought the cheap ones. Then, when this one got damaged, it's really small after pruning off the dead wood. It's no more than six inches across. I just want to jump-start it.

There are no miracles. It will take time; more than one year. Next spring you can prune the healthy ones to hold them back a little and can prune the tips of the longest new growth on the damaged one and repeat this each successive spring until they match each other in size if that is what you want. It sounded like that in your first post.

I have been doing that with some yews. The old ones were over 50 years old. One was knocked out by a car. I replaced it with 2 small ones. Buy letting the new ones grow as much as possible each year and just pruning back the tips to force them to bush out, they have finally filled out the hole that was left after 5 years. During this time I was pruning back the old ones each year so the new ones could catch up.

Thanks. I may find another home for this sad little one, and replace it because it is in a prominent place in the front bed and very obvious. That's why I was hoping to only have to wait one year for real progress.