I don't believe it has to be sold to Americans. It just can't be "controlled by a foreign adversary" (which is a very specific set of criteria in the law). [1]

There are plenty of scenarios where TikTok ends up under non-American control. Only four countries (China, Iran, North Korea, Russia) are foreign adversary countries. [2]

[1] https://www.congress.gov/bill/118th-congress/house-bill/8038...

[2] https://www.law.cornell.edu/uscode/text/10/4872#d_2