I’ve worked at places where subverting firewall rules like this would get you fired. I now refer to such situations where I’m forced to twiddle my thumbs while no work gets done as “letting the process work”.
Are you sure this is related to the cold, and not just that the batteries were fully charged so that regen had nowhere to put the energy?
[Edited to add]: I say this because I see this in all types of weather: I live on the top of a hill, and if the car is fully charge there will be no regenerative braking when heading down the hill.