This is a very sad thing to happen, because the developers don't even exist anymore. Their website redirects to another website that have ads, therefore not relevant. I do recommend you use Recuva once again but this time make sure to tick the Deep Scan and also select the folder or path where it has been stored.
I've searched the web with hope to find a solution to this problem, but it appears there isn't one. There were other users who encountered the same issue, but not solution was found as well.