Well we made some progress today. Husband & stepson worked on the car, figured out that stepson had disconnected something last year and no one had reconnected it (to disconnect the battery from everything else). So the P1639 code disappeared.
They drove around with the old IMA battery and it charged! (?? is there life in it still???)
Then they put the new IMA battery back in. No go. Some other error code (I forget at the moment). Then they took a closer look at battery and saw this wiring:
We're going to try to fix it ourselves (this would be the royal we, husband & stepson are the mechanics around here). The warranty is void as it is so breaking the seal isn't a big deal. The big deal of course is working on it safely.
I think they'll manage to fix it, but stay tuned... I was thinking maybe worst case we can use some of the "sticks" from this one and replace the bad ones in the old battery. But hopefully it won't come to that.