Yeah probably just a case where there is a delay in the refund. Happens every now and again with not just TFSource but other sites as well. Sometimes they just can't manage to get the stock they ordered.

In any event I've used them before and never had an issue. I wouldn't go about calling them a scam. They seem to be quite a reputable business. They won't purposefully retain your funds.

On a side note, given the recent decline in the $ you might actually make money off the refund!