The Russians did pretty well against the Ottomans OTL, and how many troops can the British deploy into the caucus or Crimea? The russians can mine the area around Sevastopol and plus without an eastern front (the austro-hungarians are much weaker than russia in 1914 so the "southern front" wouldn't take that many russo-german troops) the Germans have millions more troops on the western front. The British can't afford to deploy too much forces on peripheral regions.
The Entente sent close to half a million men the Macedonian front OTL, and the roughly half a million British/Indian soldiers in the Mesopotamian front, and the half a million or so Ottoman soldiers from the Mesopotamian front (and possibly a large number of the OTL Gallipoli front, though I'm not certain how many of those were transferred from the Macedonian front). Considering that the Mesopotamian front was eating a good quarter of the Ottoman military, that alone could lead to a major shift in the balance of power, even if all those Indian troops deployed to the Middle East are moved to France instead).
In the far east Japan and Russia might fight again: but the Tsarist army actually did pretty well against the Japanese army in 1905.
Japan is also in a stronger position by this point, and that 'doing well against Japan' still went poorly enough to prompt rioting across Russia OTL.
Also the wild card is going to be the Afghan-India frontier: there's almost certainly going to be a russian invasion of india ttl, but with poor infrastructure in Afgahnistan you are looking at hundreds of thousands of russians and british/indian troops fighting each other rather than millions.
Almost certainly a disaster for both sides, but Britain would be better at shaking off losses.
The military and hence political situation is hence order of magnitudes better in ttl 1914-18 than otl, easier enemies for Russians to fight, less troops needed hence less mobilization and casualties
It's definitely better, but can still easily go poorly enough to result in a revolution. Italy still going Entente for instance (don't know how you'd bribe them over, but it's not impossible) would see millions of extra troops freed up (even just a neutral Italy is a major shift for where Vienna can deploy troops). The US getting dragged in sooner would massively shift the balance. Different military strategies resulting from the varied balance of power could have a massive impact too.
Then there's the fact that it clearly wasn't just a matter of casualties. France and Germany both suffered close to the same total military losses as Russia, both from smaller population bases, and did not see civil wars erupt. As long as the Entente hold out long enough, and the Russian people see their soldiers being thrown away to die for too few victories, a revolution is plausible. In fact, moving the battle front away from the Russian heartland might well make a rebellion more likely. The more abstract the causes of war is in the eyes of the people the fewer losses they're likely to be willing to absorb.
Again, I'm not saying it's certain, but just as OTL a 1914 or 1915 Entente victory isn't impossible, so to in this scenario a Russian collapse is still quite possible.