Just to keep things clear, Eteri's mother died on november 8th. 40 day cound includes day of death, so it would be 17th november, so it doesn't even coincide with travel dates.
Also, 40th day is not a moment where people go to support the grieving relatives, but to remeber the deseased one. It is very unlikely that Alina was there, unless she was somehow envolved with Eteri's mother personally. This is usually more of a private gathering for relatives, friends, coworkers and such, unlike funeral where you can have, indeed, your friends to support you and even unrelated people who came to eat and drink. There are several remembrance days (3rd, 9th, 40th), and the whole thing becomes smaller and smaller, with less and less people.
Overall, I would say that it is debatable that Alina would not go to Saransk to attend Eteri's mother 40th day thing, and honestly, I'm not even entirely convinced that Eteri herself would stay behind for it (in my family, for instance, we never held any major 40th day gatherings, its always a small family dinner with whoever invites themselves dedicated to the deceased one's memory. So for example, in my family it would be normal and not disrespectful, if a business trip coincided with a 40th day of a close relative, to just eat alone in the hotel room and to think about the person, maybe give a couple of calls to the close family, and cancelling or delaying such a trip for a 40th day would be seen as excessively dramatic).