You're not going to find a spot they connect to and work. Key1&2 are digital SWC signal wires. The wire labeled J1850 is a single wire resistive SWC signal wire. There MUST be a converter between them. You can't make it work without one.
Oh, so your unit doesn't have the wires for SWC but you're trying to make it work with them? That's going to mean opening up the radio and soldering in to the switches on the face and then replacing the SWC buttons with regular switches instead of the SWC circuit board.
To be able to tell you if you have any SWC wires not labeled as Key1&2, I would need to see the documentation that came with the radio. It should have at minimum a list of wires. What's the model?
After all speakers, power, and such is hooked up, what wire colors remain? That unit is very popular online, you should be able to find a diagram for one. Might not be labeled with the same brand. I've seen over 20 brands of that radio.
I highly doubt the SWC method of the '12-'15 Compass is the same as an '03 T&C. Have you tried that setting? I would look for a Chrysler/Dodge/Jeep/Plymouth model of the same year range as yours if it doesn't work. If that can't be found, look for a Mercedes of the same year range.