Gacha is an unethical predatory practice designed to abuse the psychology of neurodivergent individuals and individuals who are prone to addiction. It obfuscates the cost of an item by a series of small payments that prey on a humans inability to really understand what is being spent.
Its use in gaming has been for the express purpose of generating wealth beyond the true worth of an item through exploitation. If you are going to allow this predatory monetization in your game than you might as well allow a traditional slot machine or a roulette table because they are functionally the same thing. There are no solutions that make this ethical. And lets face facts you don't have the manpower to regulate the current grid in a timely manner. This is a huge undertaking and predatory monetization and other psycological tricks will be deployed in the loopholes your policy will leave open. Like NextUp which was truly not much different than gacha.
Im sure this was a decision made by the CEO or the accountants. Im hoping you can find a way to put a stop to this. Its the right and ethical thing to do.