The ECB controls the total issue volumes, not single mintages.

I read about that 1 million mintage too, but in a collector's blog, not in any official source so far. ("Pour éviter au maximum la spéculation et pour que la pièce circule librement dans toute la zone euro, il est prévu une frappe à hauteur de 1 million d'exemplaires.") So speculation is to be avoided (ha ...); we will see.
Theoretically such a volume is possible, according to the monetary agreement: The fixed part of the annual "ceiling" is 2,340,000 euro; the variable part is the French issue volume per person multiplied by the number of people living in Monaco. There is also an option to increase that volume for a commem, but only if the volume in the year before and/or after is lower ...
Christian