I can't answer the OP's original question. But I can tell you that any answer will probably not reflect actual reality because of the vague definition of what a deserter actually is in this context. We have our text book version now, of course, but things were different on the Russian battlefields.
I haven't read a lot about WWI, but from what I've studied about the appaling conditions for the Russian troops during the Winter War and WWII, where hesitant, wounded or fatigued soldiers or simply men without equipment would be executed where they stood for refusing to immediately follow orders to go to their certain deaths, I gather that the definition of the term depended, as it did during WWII, entirely on the whim of high ranking officers. Subject to change from one minute to the next and needing no justification, of course.
I haven't read a lot about WWI, but from what I've studied about the appaling conditions for the Russian troops during the Winter War and WWII, where hesitant, wounded or fatigued soldiers or simply men without equipment would be executed where they stood for refusing to immediately follow orders to go to their certain deaths, I gather that the definition of the term depended, as it did during WWII, entirely on the whim of high ranking officers. Subject to change from one minute to the next and needing no justification, of course.