Maybe they just mean the current ones, rather than saying it has support for amiibo that aren't out yet. Maybe the game will need an update. ʅ(´◔౪◔)ʃ
There's 7 in the Mario line out (including Gold Mario) and 30 in the Smash line out right now.
If you take out the 2 Pokemon, that's 28 and 7 which is still only 35...we'd still be missing 5 amiibo with these numbers.
If you however count all of wave 4 without Pokemon (35) and counted all the Mario line duplicates of Smash without gold (5) you would get 40. So all of the Smash line except Pokemon and all of Mario except Toad (and not counting the gold variation as separate).