The risk or ruin is very small. Although quite remote, what is tragic is a long string of successive jackpots. That is very unlikely to happen though. To be honest, it would be something like a fire, flood, earthquake, war happening in the place where you have business all at the same time.
Nevertheless, you are gambling with money that you cannot afford to lose. You may wish to rethink how wise that is. One of the basic rules of operating a gambling establishment is that you *must* be sufficiently well-funded that a couple of jackpots don't ruin you.
Depending on how your customers bet, it's not unusual to have a well-run gambling establishment that has more losing days than winning days. For example, look at Satoshi Dice. You have to have the financing to let the law of averages catch up.