While the cards are numbered sequentially, you could get an estimated total run by asking people for their security codes
and then assuming the highest answer you get is roughly the amount of cards produced.
However, that list would include not only different denominations (ranging from 0.005 BTC all the way up to 0.1 BTC),
but also different currencies, there's been Doge ones, LTC ones, CSC ones, and all those weird shitcoins you and I have never even heard about.
Then you'd have to find a way to estimate how many cards have been redeemed, and how many cards "expired".
There isn't any list of public keys you could parse through, like there is for some other physicals. Getting an idea of how many are redeemed and how many are not will be nearly impossible.
So to sum up: Unclear how many cards in total, of which denomination each, and if redeemed. I doubt you'd come up with any useful number.
(snip)
I will continue looking further in to this (I have more reading to do) will be reaching out to the owners to get their take and ask why they are not honoring their promise to keep their redeeming site open until all cards are redeemed. I will be placing a scam accusation as well as flag accounts and continue to add info about that and anything else pertinent.
Else we're stuck beating around the bush not being able to fully share all information available with everyone interested and concerned about this.