What a tragedy. Seems so unfair to have ridden it only 1000 mi. You must have gotten a good deal on the bike if the repair costs are so unfavorable... not that it's much consolation.
Is the theory that the chargers went bad and somehow drained the cells?
I don't suppose there's anyone out there selling batteries off a wrecked 2013 FX or XU? (You may even be able to search years before and after if the cell compliment didn't change by swapping the BMS heads.)
If it's really for scrap, maybe I can help you recoup something from your (shippable) spare parts.
Really sorry to hear in any event.
My working theory is that the chargers or the CCU went bad, and something about the fault caused the batteries to drain simultaneously. I can't come up with any other explanation to explain how I lost 5 kWh of energy in a week while the bike sat idle in a garage.
I made a mathematical mistake in the "3x" repair cost (forgot that the price I paid was offset by my old bike). The XU cost $5000 new (factory demo) in 2015. The cost of replacing the batteries alone is $6500. Chargers would be another $300. Even if I do all the labor myself it's just not economical at all.
I will look into rebuilding the packs but I don't have any assurance that the BMS is good. I'd hate to drop a couple $k on 18650s only to have a third project on my hands. Maybe there is another way to test the BMS. Or I could go with an offboard charging solution although that really complicates charging at work.
I'll consider these options but will probably part it out. I have been searching for other '13 XU wrecks but there are so few of these things and I don't want to keep it in the garage indefinitely. It's depressing every time I look at it and I'll be much happier to get something usable in its place.