Nothing in this part shall be construed as:

(a) Affecting, modifying, diminishing, or otherwise impairing the sovereign immunity from suit enjoyed by Indian Tribes;

(b) Terminating, waiving, modifying, or reducing the trust responsibility of the United States to the Indian Tribe(s) or individual Indians. The Secretary must act in good faith in upholding this trust responsibility;

(c) Mandating an Indian Tribe to apply for a compact(s) or grant(s) as described in the Act; or

(d) Impeding awards by other Departments and agencies of the United States to Indian Tribes to administer Indian programs under any other applicable law.