Was able to talk with Doug M. at Phoenix Cruiser today - great guy. Apparently, the cable is the 120v line for the fridge.
Lance, you were correct. When my slide is extended, there are two "channels" on the bottom of the slide that extend from the outer wall, towards the inside of the coach, i.e. in the same direction the slide travels in/out. Those channels have rubber flaps (on each side of each channel) - I didn't notice those yesterday. On my coach, the left channel has the 12v cable and the 120v cable. The 120v cable is coiled to allow extension when the slide travels - that was the cable being pinched at full slide extension.
With the slide most of the way out, I could reach into the channel and pull the cable out and repair the exposed insulation. Doug had me just stuff the cable back up into the channel above the rubber flaps. One end of the cable goes to a metal junction box, to the left of the channel, and I could not feel any other cable going in/out of that box. The other end of the cable, goes down through the floor, not up to the fridge, so a bit confused by that. I suspect there was a cable going up to the fridge from the junction box and I just missed it - will feel around again, out of curiosity.
The coiled cable appears to me to be at least twice as long as necessary, so I expect there's a good chance it will end up in the same position, bunched between the trim and wood behind it, when the slide is extended. I'll be looking for a clip of some kind to anchor the cable, leaving enough on either side for slide extension/retraction, to prevent this from happening again.