They may shed the leaves, but will most likely be fine and will flush new leaves in time.
You have to think of new plants like new babies. You don't put babies outside in the sun all day the day after they are born. Appreciate how HARSH sunlight is when you or your plant is not accustomed to it.
Many of my established trees just had a similar experience. They were flushing tender new growth when we had a week of 90-95F weather with 10-20% humidity. The tender new growth could not rehydrate fast enough to compete with the hot weather and low, low humidity, so the got crispied, many dropped off, and they are reflushing now.