Actually Geoff this is all incorrect. Mercedes did not bring Lewis in because under normal rules ALL the lapped cars are allowed to re pass the leaders under the safety car. In this race only the first 5 lapped cars were allowed to pass. This was because race director wanted a car race for the final lap. But, this unfortunately was in breach of the regulations. If ALL the lapped cars un lapped themselves under safety car conditions Lewis would have won because the race would not have had enough laps left.
Mercedes based their team decision on the rule book being followed to the letter. That is what they are upset about, the fact that the race director did not allow normal race conditions to continue, which then unfairly handed the advantage to Verstapen.