$385.00 later I have a cleared sink / sewer line and a brand new garbage disposal. I also have a "shot" dishwasher.
I called Aztec Plumbing this morning and was pleased that they were able to have a technician out her at 3:00 this afternoon. Seeing that water was dripping from the bottom of the disposal, the tech determined the disposal was bad, removed it and showed me the damaged unit. When I asked him a few questions about the pipe lines etc., and asked why is it that the right side drain is clogged if it was the disposal. He looked surprised, and agreed to check it out after he installed the new disposal.
50' of snake and 30 nearly 30 minutes later, and the drain ran clear. Some of the blades were bad, as well, in the old disposal, so they weren't chopping the food up small enough.
When I mentioned that I believed the discharge line on the dishwasher was bad, he disagreed, as it hooks into the garbage disposal. He opined that it was more likely some gasket or seal on the dishwasher itself. I showed him the inspection report identifying the damaged copper water line in the attic, and he quickly added that it would be better to repipe: a proposal of $3070. Of course that's cpvc, not copper, and 1/4 turn valve and new hosebibs and braided supplies at all fixtures - blah blah blah. Oh - and for an additional $350, install a new water heater. (such a deal). I think I'll stew on this awhile.
Oh the joys of home ownership.