Given that you've stated you have ample resources, I wonder if working with more specialized doctors could help you get through this.
For example, an audiologist who specializes in tinnitus (which might take some searching), can help you identify the best device / hearing aid /masker to use and more importantly, how to tweak it to maximize its relief. They can make it as effective as possible while keeping it safe. Incidentally, there are other things these devices can do to provide relief in addition to masking.
A neurotologist who specializes in managing tinnitus could help with finding the right prescriptions.
etc.