I think a Journey audience is a pretty tough gig for Neal Schon's solo music, but I think a set built from these songs from Schon's repertoire could work:
Songs with vocals:
No More Lies (Schon & Hammer, Here to Stay)
Self Defense (Schon & Hammer, Here to Stay)
Blackened Bacon (Late Nite)
Time Again (Schon & Hammer, Here to Stay)
Covered by Midnight (Schon & Hammer, Here to Stay)
Voodoo Chil' (Hendrix cover)
Instrumentals
Le Dome/Late Night (Late Nite)
Into Your Arms (Journey Time3)
With a Tear (Journey, Time3)
Moon Theme (Journey, Dream after Dream)
When the Love has Gone (Journey, Dream after Dream)
Exotica (So U)
(Big Ocean, So U)
A Song for You (Voice)
Big Moon (Beyond the Thunder)
Call of the Wild (Beyond the Thunder)
Six String Waltz (The Calling)
True Emotion (The Calling)
Song of the Wind II (The Calling)
Prayer for Peace (Electric World)
Midnight Express (Electric World)
Urban Angel (I on U)
Moon Dust (I on U)
Cuban Fly Zone (Vortex)
El Matador (Vortex)
Triumph of Love (Vortex)
Lady M (Vortex)
Schon & Hammer Now (Vortex)
Twighlight/Spellbound (Vortex)
Unspoken Faith (Vortex)
It's actually quite a good selection to choose from, and obviously more material than he could possibly perform as an opener. These are not necessarily all of his best songs, but they are very good songs and seem appropriate for the audience. If he mixes in a few vocals each night and some instrumentals from the above list, keeps them short and to the point with no extended jams, abridges some or puts a few together as medleys, he could have a very entertaining set for Journey audiences and maybe go far to promoting some of his solo releases.