Assume the British win the War of 1812 with a POD in 1813, leaving Tecumseh alive, and after a stronger British victory, a Shawnee buffer state is created propped up by the British.
In such a scenario, how long would Tecumseh and the British remain allies? Particularly if the British feel the need to station troops, build forts, or allow white fur traders to enter the region, it seems like there are a number of grievances that the greater Shawnee Confederacy would have with the British.