If I hadn't taken the coil off my personal car which I know hasn't had any issues whether wet, dry, or monsoon, I'd be tempted to look at it again. Heck, at this point I'm considering looking at the plug wires again even though they're brand new and Magnecores on top of that.
As an update, I did try to go out and liberally squirt down the electrical connections and plug wires to see if I could cause a misfire with the squirt bottle and no such luck. I might try again when the car is stone cold since it had only set a few hours when I tried tonight.
Rick