It's been a while since i installed my armrest so you'll have to
forgive me if this isn't entirely correct but if i remember correctly
you should have the armrest itself, 2 metal brackets (one that bolts to
the console and the smaller one that bolts to the first bracket and
holds the armrest to that....part no.s 27 and 30 in the above diagram.)
and assorted nuts and bolts.
If you're missing these bits you
can buy a repair kit for the armrest from vw that includes all the
brackets and bolts that you need (it's what i had to do with mine coz i
bought a crappy ebay one on which the brackets were sh!te and the bolts
didn't fit in the brackets or onto the console, or the armrest for that
matter.....and the armrest itself wasn't much better seeing as it broke
as soon as i leant on it) for about $28 (edit: that should be the
pounds sign but the button is knackered on my keyboard).
Like i
said, it's been a while since i did mine but iirc the 2 holes you
describe is correct and the bracket is secured to the console on those
points by u-shaped clips (number 34 on the above diagram) that holds
the bolt like a nut does (look at the clips and screws holding your
wheel arches to your front bumpers to see what i mean). The third
mounting point is on the securing bolt from the handbrake. You have to
remove that nut and replace it with an elongated one (part number 33
above) supplied in the repair kit.
I hope this makes sense, i
have read it back to myself to make sure but i have the advantage of
knowing what i mean. If you've got anymore questions i'll do my best to
answer them and if i get the time tomorrow i'll take the console cover
off and take a few pics, which would probably explain it better. If it still doesn't make sense though, i'll happily buy it off you if it's an official one 
Hope this helps
Ben