Imperial Germany aided Lenin's take-over of Russia, so it's not totally beyond plausibility.
In 1914 Lenin was in Galicia and arrested for being Russian. Although he was released he was forced to go to neutral Switzerland, the Tsar's secret police would have arrested him if he had gone back to Russia.
In 1917 when the February Revolution occurred a number of Russian exiles (including Lenin and his wife) requested permission to travel through Germany to the coast, where they went by ferry to Sweden. Then onto Finland, then St.Petersburg. The condition of the German government was that the train should "closed" - they weren't allowed to stop and get off the train during the journey, or allow anyone on to it. The decision was undoubtedly made because the people involved advocated that Russia should pull out of the war.
Lenin was back in Russia in April 1917. It was not until the summer of 1917 that he openly advocated the overthrow of the Kerensky regime. In part because Kerensky wanted to continue to fight the war.
There was no civil war in 1917, nor did the German's "support" the Bolsheviks to seize power in the coup in October 1917. They neither needed nor wanted support from Germany, they had the support of major sections of the army and navy and the working class in the cities.
The first stage of the civil war broke out shortly after that, in Finland. Nationalists declared independence from Russia, and communists then seized power in Helsinki and other cities. The Finland nationalists, including Gen. Mannerheim, then crushed the communists with German support. IIRC three full strength Divisions were sent by Germany to Finland in early 1918. Around the time that the new Russian government under Lenin were negotiating peace terms with Germany.
Germany got peace in the east, but couldn't send enough of the Divs that had been fighting there to the Western Front to force the issue in France before the US forces started arriving in large numbers. By then Germany also realised that the revolution in Russia could spread across Europe, and revolutionary forces became active inside Germany. The defeat of their offensive on the Western Front, and famine, led to the downfall of the Kaiser and his government.
It's difficult to say what might have happened if Germany had not allowed Lenin's train to cross their territory. Whether France or Italy might have allowed passage. But allowing a train to pass is hardly the same as providing money, men and/or equipment to fight a civil war. It's not like the German's sent a Condor Legion type force to fight for the Reds against the Whites in 1918-1923.