Nice job and nice location Jason. You really jumped on it!
Like 'ivanford' indicates you probably just grabbed the wrong wire. It has happened to me at least once. The wires can be difficult to expose and those colors can be tough to see in different light. Actually all four MDS solenoid wires are there at the PCM. The brown/light blue coming out of the C1 connector (as described in my DIY) goes to cylinder no. 4's solenoid, the brown/dark green coming out of the C2 connector goes to cylinder no. 6's solenoid, while the brown/white and brown/orange coming out of the C3 connector go to cylinder nos. 1 & 7's solenoids, respectively. You can grab any one of the four and get the LED to work when in the MDS mode.
"If at first you don't succeed, try, try again!"
2005 300C BRILLIANT BLACK, DRL, Mesh Grill/Vents, Chrome Pillars & Fender Trim, MDS Indicator, Quad Brake Lights, Tinted Windows, De-Molded, K&N Aircharger, 180 T-Stat, Flashing Sidemarkers, Predator Cust. Perf. 93 CAI Tune
1997 MUSTANG COBRA 'VERT, TRIPLE BLACK, Vortech S/C'd., ECT Mod., 4.10 Rear, 18" Saleen Wheels
1950 FORD TUDOR FLATHEAD V8, FLAT BLACK, 54 Chevy Grill, Nosed/Decked, Frenched Headlights, Air Shocks, Three-On-The-Floor w/OD, Dual Glasspack Exhaust, Dual Two-Barrel Carbs