Both sides of the boundary, at the time of the survey were Indian Land. Townships weren't surveyed in Oklahoma until the 1890s. I don't think the Osage Reservation in KS was surveyed into townships until after the war when the Osage were moved to OK. The only way the surveyors and astronomers could determine their precise position was by sextant. Boone's party must have used a sextant to determine their location and miles traveled but would have lacked the precision of Johnston's astronomer team.

Johnston et al were on their return trip when they came to the Salt Fork etc. They started at the MO line and went west. On their way back, they came via the Cherokee Outlet (maybe to avoid Osage) and into Cooweescoowee District of the Cherokee Nation probably just north of present Skiatook OK and camped near Mr. Keyes [I assume Leroy Keyes, a prominent Cherokee of the District] place on the Caney. In late 1861, Cherokee Col. John Drew reported that jayhawkers from Kansas had stolen cattle from Keyes Settlement and Drew's cavalry chased them until they abandonned the cattle and slipped away into KS.

Out west at the Great Salt Plain, there wasn't anyone to enforce any rules and many tribes got their salt there. It was also a well known meeting place for the tribes. At the time, it wasn't a reasonable commerical opportunity due to transportation. The valuable saltworks were in eastern Indian Territory along the Grand and Arkansas Rivers. In the early 1840s, the Cherokee Nation nationalized the saltworks and then leased them to new operators -- lots of politics involved.