They have signed the agreements with provision, suggesting they

to side with the U.S., not China. 

The U.S. has the upper hand because Wall Street controls capital flows. If these countries do not side with the U.S., the U.S. may threathen to sanction their companies, and Wall Street can halt the dollar clearing of these companies, ensuing the sanctions.

Yuan is not a free floating currency. International trades are settled in $$$.