Good choices. I think you'll find that Jed (familiar) and Foggy (fast and with "hooks") will do the best. Also, Cripple Creek is catchy, Dear Old Dixie has good chords and the hook on the "stop". Lonesome Road will sound more generic (not bad necessarily), but John Hardy, as a "lick vehicle", can easily lose out as a way to engage listeners, who need more in the way of catchy melodic elements. If you and the mando can play clear and strong on Turkey, that will be some nice variety.
If it’s not too late to round up a decent fiddler, that would not only sound good, but look good. After an hour of nothing but picked instruments, it's really nice to hear a bowed one. And think of a slow piece to do now and again, just for variety for you all.
How you all look while playing is a pretty big element for this type of gig. I don't know exactly what "the part" is, but you should all make at least some effort to try to look it. Probably denim, maybe boots, maybe some kind of nice but not too flashy western shirt, and a decent hat of almost any kind for those who have them, would do nicely. Part of your value is scenic, and don't forget to really have some fun, or at least try to look like it. Those who can, should try to make some eye contact with, and relate to, the crowd in any way that works.
As a performer, especially in a somewhat symbolic, and visual situation, I recommend trying to stretch beyond the usual blank look that people have when jamming. Look at each other, be somewhat animated, encourage each other verbally, smile if there's "anything" worth smiling about. Not a bad idea to go Yeehah once in a while which if done in various ways will make you all grin. In short, get a bit into the heads of the audience people, kids and grownups alike, and think of what you enjoy doing that they would like too. It should come out just fine, and if it is, they just might hire you every year.
Have a blast!