Soooo, soon after Enterprise E arrives at the Bak'u world, the crew begins to rejuvenate. Picard grows dark stubble, Worf gets a zit, Geordi gets new eyes, and Troi/Crusher get... well... firmer.
Why doesn't this happen to Admiral Dougherty? Or to the Sona for that matter? They've been there weeks, perhaps months longer than Enterprise.
They state in the film that it takes more time to repair the damage the older you get.
And besides, who knows how old Dougherty appeared before he entered the Briar Patch?