I want to thank you all for your help and to let you know the final results. That was my first foray into looking at the innards of a battery pack, so your patience is much appreciated. Well 10 out of the 12 cells were at 3.4 - 3.5 volts. There were 2 cells that were at 1.0 v though. I used a couple of phone chargers to get them into the 3.1 v region before I ran out of time (had to send the bike back with a friend that was visiting as I was giving it away to him). Well, I hooked the charger up, and it just took off like it is supposed to do. You all were correct that it was the BMS that was keeping the charger from charging and the pack from discharging since there were those 2 low cells.
The next morning, the battery was showing a full charge, and I instructed my friend to leave the charger one for several more days to ensure the BMS had time to do its balancing. All was looking good, but then we found that the charge just wouldn't hold. One of you mentioned that there might be swelling, and indeed that is the case. I have since learned that a prolonged period of discharge (especially when the battery has previously been over-charged) will result in swollen cells. When I took off the duct tape, it was quite apparent that swelling had occurred. I also learned that this is a bad, bad thing
I took the logical next step and ordered a new battery.
Chalk it up to an expensive lesson learned, but I will now be far more vigilant when it comes to caring for my batteries!
Thanks again for all your help. It was a fun project to try and ressurect the battery pack, and I learned a lot in the process.