You probably already have the answer to this, since it was a week ago that you posted your message.
When we damage plants, yes it happens...especially with new employees! We leave them for a week, and by then, when the crew goes back for service, we hand prune off the fronds that are turning brown. Those that don't are still gaining nutrients and will return on their own. I'd leave those alone and baby them along.
Mitchell J McGowan
Dotdirt Organic Landscapes,www.dotdirt.com