You posit a false dichotomy.
It is absolutely possible that Mr. Smith wholly supports the position of Ms. Khan, vis-a-vis Indigenous rights, yet disagrees with her use of racial discrimination in the effort to address the issue.
I support much of Ms. Khan's cause, but entirely, and unequivocally believe her statements were intentionally racist, and entirely destructive to both her credibility, and her cause.
The terrible situation of Indigenous persons in Canada (and much of the world) needs fixing.  But fighting blatant racism, by promoting blatant racism, will do nothing to see this end.  In fact, it favours the status quo, as it will make an "Us or Them" situation, and the power base most able to assert their will, always wins.
This issue requires compromise, and fair dealing, not tit-for-tat racial attacks.