Why an EV must never be flat-towed
On a gas car, towing with the driven wheels on the ground is a lubrication problem — the transmission spins without oil pressure. On an electric car it's an electrical problem, and a worse one. A motor whose wheels are turning is a generator. With the car unpowered, that generated current has nowhere to go, and the result ranges from a fried inverter to a destroyed drive unit.
Dolly towing has the same issue unless the raised axle is the only driven one, which on a dual-motor EV — most of them — is never true. Every manufacturer specifies flatbed transport with all four wheels off the ground or on skates.
The second issue is the parking mechanism. Most EVs lock the motor when unpowered, so the wheels won't turn at all. A general operator who tries to winch a locked car onto a bed drags it, flat-spotting tires at best and damaging the drive unit at worst.