Stromer BQ983 System error 0x210003 and Battery Error 0x210008. & options for aBQ983 rebuild?

First does any one know if these errors are related? One is a system error the other is a battery error.
Second, does anyone know anything about the System 0x210003 error?
Background: I was charging a relatively new BQ983. I got the 210003 error. and a fried battery. I asked the dealer and he said it was a battery error. However, I hooked another BQ983 to the same charger and got the same error with a different battery. I was able to save that battery.
Here's my speculation: I think the thermostat went out on the charger and the cooling fan didn't come on and perhaps backfeed protection problems. As all you Stromer owners know the BQ983 is $2K. The one that got fried only had about 4k miles on it. It came with a used ST2s I bought. . . so it's not under warranty. Any suggestion about a rebuild? I can post pics of the error, if that would help. Many thanks for taking time to read this. I'm looking forward to some great feedback
I found the following entries in my error table for E210003.
SUI FW | 11.03.2022
>> Sometimes the error code "210003" was displayed when the Stromer was switched on, because the battery or the power supply was switched on with a delay. Newly the error is cleared when the power supply was switched on successfully.
The dealer will find the 6x error code E 210003 in the service menu, which indicates a bad connection between the battery socket and the controller (MCU) in the Stromer. The so-called wicket cable must be checked. It may also have a short circuit and damage the battery or the MCU.
There is no entry for E210008, unfortunately.
I cleaned both ends and it worked. I should have done each and tested in between. I suspect it was the battery, as it always only happened when I was switching out batteries; however, I cannot say if the one I switched out was the same every time. With regards to the battery error code, it may have something to do with the battery overheating. Or shall I say the charger fan going out. I left the battery in the bike and charged it and it appears the fan on the charger never came on. I'm lucky there was no fire, as I believe a Strumer dealer had the same issue, except he did have a fire. I totally understand that you should never leave the charger plugged in for over extended periods. But I thought overnight would not ruin the battery. Now I charge the battery outside of the bike and I monitor the charger to make sure the fan comes on.