hi there!
It almost sounds like the support is not well aware of the problem, and based on the fact you could not locate the game later, it could be something related to the game provider.
I imagine it must have been frustrating. If I were the casino support worker, I would do my best to find decent compensation for you., just to ease your negative experience.
Truth to be said, many casinos include in the terms that in case of technical bug, the winnings are not valid. Yet, it is always preferable to explain the circumstances fairly to the player and, for instance, compensate for the lost bet.
Could you tell me what you have been told this far by the casino workers?