Boro's new £2m signing from Sparta Rotterdam has, however, been left on the standby-list by coach Foppe de Haan for next month's tournament in Beijing.
Emnes should now be free to take part in Boro's full pre-season programme.
The 20-year-old attacker would have missed the majority of Boro's warm-up games and preparation for the new campaign - as well as the Premier League opener against Tottenham on August 16 - if he had gone to China.
Emnes is set to be part of a senior Boro squad who visit York City in the first pre-season game on Friday.