Yes. DJs outside the United States can use Digital DJ Pool. The service is based in the United States, but access to the pool does not create permission for every possible music use in every country.
Copyright rules and permissions can vary by location and by use. Review the Digital DJ Pool Terms and check the requirements that apply where you plan to play or share a track.
A DMCA designated-agent registration is a way to receive copyright notices. It is not a government license for music use or a certification that every track is cleared for every purpose.