The use of "nations" in that comment is not clear nor substantiated, not in the comment itself, nor in the article. So just to be clear that DB is not tied to a nation, even though the name suggests it is.

OP means the USD & US nation is not stable, hence DB looking to clear Yuan.

Do you also make this clarification whenever Bank of America is mentioned, such that no one is confusing it with the FED?

And do nations use Deutsche Bank's services?

Yes. For instance, the National Bank of Ukraine has an account at Deutsche Bank.