I don't think the plug would go in without the earth pin missing, as this is what opens the tabs in the socket for the L and N pins to go in.
I'm confused with the bit he left? Usually a 13amp plug to a cloverleaf which plugs directly into the charger. If he left that lead behind, what lead is he butchering?
On some sockets the protection is provided by a rotating shutter that needs equal pressure on both live and neutral - so it is possible. And also if someone has some of those ridiculous "socket protectors", that can be use to open a socket ... TO me, it is good practice to destroy any moulded plug when it is cut off irrespective of the reason.
here's a link to the foreign colours and relevant standards http://openelectrical.org/wiki/index.php?title=Cable_Colour_Code
i always hack to bits any moulded plug i have had to cut of (not due to a fault in the appliance) also i save the fuse and the cover
I always save the fuse, they are 14p each. Regarding the colours, if it was me I'd take an educated guess and connect them to a new plug, what can go wrong. A word of experience, if you take a laptop switched mode power supply to bits to try and find out whats wrong with it keep in mind the chassis of it, i.e. the heat sinks the triacs and such like are fastened to are at 240V potential, here speaks the man of first hand experience.
I had a flight case full of 13amp fuses removed from FCU's, or plug tops during pat tests. Thousands, easily. My misses used them at school, with hot melt glue, to make a random sculpture!