BitSpend was just as lame. I've recently had a similar problem with GiftCardZen, but for a relatively small amount.
We found where the transaction went - to a wallet that has more than 6200 btc in it !!!
https://blockchain.info/address/19mfTX5NpwwYjLqbAM8BQAxsNgfd7GESc5
Since the vendor canceled the order, SnapCard isn't out any fiat for it either.
My guess, it turned out to be like a Ponzi: they used the btc they got from this order to get the the fiat to buy your stuff. However, because this order was delayed due to some vendor inquiry, SnapCard ran out of fiat by that time due to the exchange rate correction.
So, they decided to just quietly let the order cancel and stop responding to emails, like a teenage girl who stops answering calls from an unwanted suitor, hoping he will eventually get the message...
Based on this and my own experiences, I will only send btc directly to a merchant if that's all they accept. Otherwise, I'll turn it into fiat first, where I have recourse if they don't deliver, and avoid retards like SnapCard, and other lame btc merchants.