From what I know, they didn't ask questions then. they didn't demand answers. Yes, they are now (to an extent) but back then? one of the hikers was yanked from the trip because he didn't spend enough of his vacation helping others. Now does that sound like a government that people argue with. Not to mention the comment in the diary that they didn't have a choice when his replacement joined them? Not buying the "they had choices, they could ask questions" but honestly, unless we lived it, it is all supposition.
It wasn't that Bienko was yanked from going due to not helping others; part of being a student was paying off your labor debt for them sending you to college. Bienko had spent all of his vacations hiking. He was getting a free ride to college while blowing off the responsibility of his labor debt, which was the agreed exchange. He absolutely understood because he knew he had been blowing it off. If the government was so authoritarian, would they not have forced him to do his labor debt well before then? Or arrested him for thievery for taking his education and not living up to his side of the bargain? Yet they did not. If the government was so harsh, would two of the students have brought illegal weapons on the hike? Would the hikers have bent the truth about dedicating the hike to the Communist congress in order to get Rustem and Krivo out of work? Would Zolotaryov even be allowed to go, since his brother was an enemy of the people?
The reality is not the black and white we often think of it as.
As for the families and friends asking questions, Rustem's father made quite a commotion demanding the authorities find his son and figure out what happened. Kolevatov's sisters did the same; Rimma contacted people in the local Communist party and even contacted Moscow directly demanding they intercede. Read Rustem's fathers witness testimony; he was SCATHING toward the "powers that be." He did not disappear. There were a LOT of questions asked then. Heck, even Ivanov, who was read the riot act by Moscow, wasn't "disappeared." He went on with his career. The UPI staff who were blamed for the disorganization of the group, got slaps on the wrist and the only person who was fired was then rehired like nothing had really happened. He didn't disappear and he lied to the authorities about receiving a telegram from Dyatlov saying he'd be late.