Unfortunately I don't see how the throttle control is related to the heated Oxygen sensor except through the ECU. The wiring for the throttle is not exposed to road damage so it would be unlikely that its harness would have been damaged at the same time. Also, the Oxygen sensor heater is only activated for a few minutes after start-up, so it is off most of the time. If the heater circuit was shorted it would not have damaged the ECU until the next time you started the engine. Be sure to sort out the Oxygen sensor harness first.