Considering that 1) Milo's own Amulet of Protection from Evil was cursed so that Tom Riddle could keep possessing him, and 2) every Amulet of Protection that Milo made for the Ministry was made in that period where he was possessed by Tom Riddle, does Milo

He has no guarantee that they aren’t cursed. Probably the best way to check if they were is to cast Analyze Dweomer or a similar spell, though he’s actually too low level to do that currently.

Without knowing the command that triggers the curse effect (if, indeed, that is the issue with the amulets) it would be very difficult to find out which are cursed and which are not.