Im pretty sure Alska would be occupied during the Russian civil war. The question is what happens to it later.
1. On one hand I think it highly unlikely that the soviet government will acknowledge whatever the occupiers decide to do with it
2. Any finite step in this regard would lead to serious troubles with the soviets - thus i find it not unlikely that if initially nothing other is done than ocupation that will remain the case up to WWII.
3. If step 2 happens I think it likely the soviets get back Alaska during WWII - because sure as hell they would ask for it and it would be very strange not to comply. This - the soviets asking for it will happen irrespective of step 2 now that I think of it.
TLDR whatever happens in will be brought up and used as a bargaining chip in WWII by the soviet side. They will either agree to get something else in exchange or get it back.
If WWII even happens as OTL, and if the US agrees to give the thing back to the USSR, it would be with some kind of demilitarization agreement and probably even with US basing rights of some kind.
But WWII isn't happening as OTL and the USSR isn't demanding Alaska back in WWII even if it does happen as OTL>
Most likely outcome of the Red Revolution is the US/Canada set up some kind of remnant Russian state. The equivalent of Taiwan. And recognize it instead of the USSR. This may or may not affect some of the investment and commerce that US businessmen did in the early days of the USSR. And that may or may not have some long-term effect. But it almost certainly prevents FDR from recognizing the USSR in 1933 as in OTL. Which could mean things like no lend-lease and a pretty different WWII. If FDR does manage to resume relations with the USSR, it will be part of a deal where Russia is forced to agree to Alaskan independence.
That's assuming everything looks the same more or less up through the Russian Revolution.
But it won't.
Having Alaska be Russian will change the Klondike Gold Rush, which will in turn have effects on Russia.
Having Alaska be Russian will have some effects on the Tsarist naval and military strategy and their expansion and development of Siberia, which could change or even butterfly the Russo-Japanese war. Which has huge effects on Russian society. Which, combined with the possible diplomatic and political consequences of Imperial Russia being in the backyard of the US and of an important Dominion, could and probably will butterfly or change WWI. Which means no or a very different Russian Revolution.
It is not literally ASB to have a cold war like OTL with the USSR having Alaska. But its not going to be OTL with that one difference. It's going to be a convergent timeline where a bunch of different stuff happened, but then even more different stuff happened that converged the divergences.