There's a high possibility that it will be a big deal on the part of the employer so before anything worst may happen, its better to get you transferred into another department wherein money is not directly involved. That is not only for the welfare and peace of the company, but it will also do good for you. Because once a gambler, will always be a gambler, and if you can't beat gambling addiction, that will be the start of seeing yourself in huge loss that may affect even your work.
You are right, because logically we will be transferred to the part involved for financial access or transferred to another company affiliated with the previous company. Because the employer has thought about the negative impact if he allows the gambler to manage the finances it will certainly not be effective, because the gambler has the opportunity to do something bad one day without being planned because of the high loss factor in gambling.