I now have the 2000 dome version as well.
I had to ask the person who sourced it for me, how I tell it was minted at the dome besides the holder saying it.
Seems it has a dot/blob on the reverse side.
I could not get a good picture of mine...so here is one that a google search returned.
So the versions are:
obverse dated 1999 with the standard reverse
obverse dated 2000 with the standard reverse
obverse dated 2000 with minted at the dome reverse
Ken