THere is no doubt that the car's original ICU and upgraded OVP relay were removed from the car. Whether the dealer or the independent shop did is unknown and is a separate problem; likely the vehicle was used as a parts donor car and the original parts were for whatever reason not reinstalled. It will be difficult to point a finger at this point since the two services occurred over 6 months ago.

The cost of the control units warrants confirmation of the defective status of the existing part prior to its renewal, so I'm at a bit of a standstill until I can obtain a unit of known quality to swap in.

Fresh paste was installed on the bottom of the ICU when it was removed for inspection. But it seems lack of paste would manifest itself as a potential probelm once the ICU was at operating temperature... which is not what is seen in this case: the vehicle misses when started cold; subsequent restarts when warm yield a smooth idle.

Tends to suggest an electrical problem, where something is not making contact when cold.