Unless you have played hundreds of times any estimate of the odds will almost certainly be a poor approximation to the true odds.
The Black Friday game was more attractive, because you did definitively win first a card and second a joker after a certain amount played.
In this week's event, I played 151 scratch games.
I did not win any cards which is probably because of having a rather complete collection.
I won approximately 9 times 50 credits, and 1 time 20 credits from the bonus box.
At times I was as low as 85% return on my gambled amount.
I stopped the game after the last win of 50 credits, and ended up with 95% return.
The game this week might be most attractive for members seeking to win special event cards, and for members on lower levels because they may win discounted cards. It is not really attractive for members with rather complete collections.