~snip~
As far as I know they will never be able to fix everything, I have never heard of a casino doing something like that and being able to fix it perfectly, even when someone fixes it the trust will not come back, they still have a bad history that is a concern for many people and communities, especially people who are affected by their unprofessionalism in running a casino.
It is not easy to fix the trust of the customers but they still have a chance to get it. But they must prove to their customers that they are working on that and fix one by one of the problems.
This is why a business needs trust from the customers and once their customers don't trust anymore, the business will difficult to grow and raise its reputation. But that can be done if team is serious about changing the situation.
The correct sentence is (therefore every casino must maintain the trust of its customers) that sentence is better, because if trust is broken, it is very difficult to restore it.
They still have a chance in the eyes of new customers, but it is undeniable that when gamblers are smart and more selective in choosing a casino, they will look for the casino's track record in the past for their place to play and if it has a bad track record then don't expect too much they get big and smart customers.