A Federal Government which does nothing can expect to have bloodshed on its hands, as the civlised tribes form up their own militias and start defending their own borders. They've got the technology, they've got the money and they've got the motivation.
If John Ross knew that Washington wouldn't protect whites illegally migrating to his nation, there can be no surer outcome than that he would start removing them. Cross border outrages would become the norm, and a state of war exist between Georgia and the Indians. Expect attrocities on both sides.
This may lead to an earlier secessionist movement as Georgia settlers rail against a useless Washington government which does nothing to protect them from the savages on their borders. The other Southern states would take note.
Alternatively, a Federal Government which intervenes decisively on the side of the Indians incurrs the wrath of the nation as a whole. The press - even in the comparatively liberal north - would have a field day decrying a government which props up the Indians in the face of white Americans. It's likely that this government would be voted out and replaced by one happy to change the laws.
I suppose, really, it depends how the exact circumstances transpire, and which side has the best PR. But there are going to be major ideological issues surrounding the defence of Indians against whites by the Federal Government. In an openly white-supremacist country, whose sole avenue of expansion is westward, it's highly unlikely.
That said, I could see a situation where John Q. Adams holds onto his presidency for a second term. He would personally be inclined to favour the Five Civilised Tribes, and had a history of sticking by the letter of the law even when it was contrary to his own interests. He *might* be inclined to deploy federal force to protect the Five Civilised Tribes.
This would set an incredible precedent, and define the relationship between Washington and the Indian tribes in much clearer, and more equal terms. 'Domestic, dependent nations' would be no mere legal fiction, but a de facto reality complete with recognised borders and legal protection for the Indian nations in question.
The question is whether or not this precedent would hold: after his second term, Adams would leave/be removed from office, and someone else will take over with much fewer qualms about removing Indians. You'd really need two men like JQ Adams in a row for the policy of protecting Indians to become anything like permanent.
Thinking ASBs, If it did, you can expect westward expansion to continue, but on much better terms for the Indians than those which they got in real life. There will still be unequal 'Beads for Manhattan' treaties, but there won't be squatters occupying unceded Indian land, backed by Federal forces. That alone is a disincentive to head west. The US will reach the Pacific, but settlement will be based on interconnected strings of towns and villages strung across recognised and protected Indian territories. Many less states will be formed, or smaller states, and the body of population will remain concentrated along the Eastern Seaboard. On the other hand, I would anticipate that such legislation won't have much effect in places with a minimal Federal presence (California springs to mind).
Regarding the Five Civilised Tribes: I doubt they'll have any incentive to petition for statehood if they're protected as a 'domestic, dependent nation'. When the Civil War comes, it's likely they'll outright declare for the Union in recognition of the protection they receive from the Federal Government. So the Confederacy will have a big cuckoo in its nest from the very get go, unless they can offer them genuine guarantees that Indian land is safe from white encrocachment under the same terms as it was under the Union.