The 19-year-old has been replaced in the squad by RB Leipzig's Oliver Burke as the young Scotland side prepare to take on the Czech Republic, Brazil and Indonesia over the coming week.
There will still be plenty of Brentford involvement in the prestigious youth football tournament with Ellery Balcombe and Chris Mepham representing England and Wales.
Elsewhere, John Egan has been confirmed in the 19-man Republic of Ireland squad for their game against Mexico at Metlife Stadium, New Jersey, which kicks off at 1am UK time on Friday morning. The match is the first of three games for Martin O'Neill's squad in June which culminates in their crucial 2018 World Cup Qualifier at home to Austria on Sunday 11 June.