Your voltages don't seem to be any different to mine or several others, who have 100% SoH.
Clearly the SOH is not calculated based on the fully charged voltages.
We still really have no idea though how it calculates the SOH unfortunately, we can only totally speculate.
That is why I was wondering about the resistance figure, I've not seen and collected this data from people before, so can't comment if this could be related somehow.
I do wonder if the voltages could be used to set a known voltage range, the computer then figures out how much power (kWh) it obtained from the battery over that voltage range.
They will have a known battery capacity voltage curve for the cells used. Therefore on a new battery, they know that if it is discharged from X voltage down to X voltage, how much power will be obtained from it.
The computer constantly knows how much power is being pulled from the battery (it also knows how much is put back in from regen to subtract that amount), if it keeps track of this in regard to what the voltage goes from/to, it could then compare this to what is expected from a new battery.
It is very hard to keep track of the originally stored battery power used, as unlike on some other cars we don't get shown how much was regenerated in the trip computer.
I'm not sure how/if this data can be obtained from all the known OBD2 queries.