Bad battery cell?

The problem is that the edriver-bms is not available due to the worldwide chip-shortage and edrivers time. If the try with the original bms fails, there’s plenty of time to wait for the delivery of the edriver-bms. I prefer to keep the things simple, building a cellpack is difficult enough…
I would like to put time into a battery-project when I can purchase an old battery. Still didn‘t find one….

@udo229:
These are valid arguments.
But in "urgent cases" I'm sure that it will be possible to get an unused edriver-BMS of the first charge.

I have signed me up for the eDriver BMS, But maybe it is not a bad idea to try out the orginal BMS while waiting.
We don't know much about the orginal BMS. Probably the worst what can happen with the orginal BMS is that the full capacity is not available. Also I wonder what the SOH indicator will do.

So far 3 options:
- Orginal BMS
- Virtual BMS with another real BMS (complex)
- eDriver BMS

My only concern is battery cell 9. Only way to find out what is going on with that is to open the battery first. Maybe the cell is fine but the BMS isn't.
Anyway, I'm not scared to start the battery adventure. Its an perfect winter project. I don't need my Twizy for daily use, I only drive it for fun.
However, before I start I will make a good proper plan.

Moneywise, I tought of building a battery seperate next to the rental one. But paying off the rental contract is cheaper than the batterybox w/o electronics itself.