Okay, Lira goes. No problem!
It still makes sense that Gorby and Anson stay at the settlement with Uien and the others.
As to what they do while they're there, I really don't see why you can't be as creative as you like outside the linear story line. You could have them do a Merry and Pippin discover-the-pipeweed (or whatever) type of scenario. You could have them get attacked. You could have them see something in the water, whether a swan that is a long lost descendant of Luvien Tinuviel's swans (did she have any? I don't know), or a wet balrog. Well, okay, I'm getting carrried away in those last couple. Keep it true to the fourth age, but heck, have fun with it.
I know! You could play a form of "20 questions" with the prisoners (former captors), trying to find out what and/or who the Master is and what he's up to, and I'll speak for them, and mayyyyyybe we'll find out early enough to have someone go galloping after the original party with "special intelligence". Or not. Just an idea. Do what you like, but feel free to post and have fun with it.