My mistake: it was Lake Num-To, and it is still forbidden for women to visit the sacred island there. The trouble started when a Soviet fishing collective was fishing in the lake, which was also not permitted at time. I apolologize for the wall of text, but here is the relevant passage from the article. What do people think about the detail about the Soviet men being "throttled by long ropes around their necks"? Any similarities to the injuries of the Dyatlov group? (The author of the below is Art Leete, "Religious Reactions to Power in Siberia"):
At the end of the meeting, two shamans organized a reindeer sacrifice (pory) and fifteen animals were killed. After the ceremony the shamans announced that the spirits (lunkhs) approved the decisions of the meeting and ordered that nobody was allowed to cooperate with the Russians. Those who met the Russians’ demands would be punished (GMPICH, Loskutov 5, 1. 6; Golovnev 1995, 168; Balzer 1999a, 111).
There were several more similar sacrificial rituals held from 1932 to 1933. In 1933, members of the fishing cooperative from the Kazym culture base began to fish on Lake Num-To. The local people informed them that this was taboo.6 Russian agitbrigades were sent to the area (GAHMAO, Astrakhantseva 1934, 7–8; Balzer 1999a, 112–13). One of the delegations reached Num-To in November 1933. A member of this group, a female communist named Shnaider, went to the sacred island in the middle of the Lake Num-To, ignoring the local peoples’ beliefs concerning a taboo on women visiting this place. Her action deeply hurt the religious feelings of the local people.
Then the Soviet delegation moved to the tundra belt, and on 3 December they met the Khanty and Nenets. On 4 December members of the agitbrigade were taken prisoner by the local people (GAHMAO, Astrakhantseva 1934, 10; Balzer 1999a, 113–14). The Khanty and Nenets held a shamanic séance after which the shamans stated that gods had ordered them to offer the captured Russians as a sacrifice. The Russians were tied up and taken to a hill by reindeer sleds. They were throttled by long ropes tied around their necks. After the killings, the Khanty and Nenets sacrificed seven reindeer and held a traditional ceremony (Budarin 1968, 226; GAHMAO, Astrakhantseva 1934, p 12–13; GMPICH, Loskutov 1, p 24; Loskutov 9, p 8; Balzer 1999a, 114).