The Allied intervention (with the possible exception of the Japanese) were half-hearted at best. The Allies were tired from the First World War and preoccupied with the matters at the Paris Peace Conference. There were also significant opposition to the Allied intervention eg from the leftists and labour union. Wilson and Lloyd George also disagree with the intervention IIRC. The Allies leaders couldn't agree on how best to deal with Russia or if they should intervene at all. Decision making was made more difficult by the fact that the Civil War wasn't between Red Bolsheviks and White Royalists - there were also anti-Bolshevik leftists, liberals, local farmers, nationalists of various kinds, etc - it was a situation in which, seemingly, anything can happen. Even among the Japanese leaders there were no clear goals. The White forces were divided among themselves and spread out across the vast expanses of Siberia, whereas the Bolsheviks controlled the industrial and population heart of Russia. This made coordination, etc very difficult.
The Allies IIRC never got close to Leningrad or Moscow. The French briefly occupied Odessa, the British and Americans Murmansk and Archangelsk and the Japanese parts of Siberia. The Japanese never got as far as the Urals - the closest they got to IIRC was Chita, east of Lake Baikal. The Japanese did hold Vladivostok and other Russian territories around Khabarovsk though. The Japanese did have plans for a puppet regime in the Russian Far East. What would've materialised would be a Republic under heavy Japanese influence controlled by White Russian generals (Under Alexandr Kolchak perhaps? I'm not sure how he views the Japanese though. Generally Russians at the time tend to have very negative views). The White Republic would've covered a substantial part of the Russian Far East - Vladivostok, Khabarovsk, perhaps as far as Chita, Yakutia and Kamkatcha). North Sakhalin would probably be annexed. A Pro-Japanese republic in the Russian Far East would damage relations with the other Great Powers however, and the United States in particular (which sent a expeditionary force to Vladivostok to counter the Japanese).
As for the question whether the USSR will exist, that depends more on the outcome of the war in European Russia. White victory IMHO was very unlikely. The Bolsheviks were well-organised - their enemies, although may be quite powerful if they unite, were not. The Allies were war-weary and not committed to long-term goals in Russia, and many in the West were actually sympathetic to the Communist.
