Another possible snag could be the material required for the translucents.
Normal buttons are made from a Nylon material which is relatively soft, somewhat flexible and self lubricating to a good extent.
On the other hand, the translucent materials are usually harder, more brittle and would probably require a release agent to be used in the de-molding process.
Plastics are usually not thought of as abrasive materials, but they are. Injection molds have finite lifespans (admittedly in the 10's or even hundreds of thousands) but their longevity can be greatly affected by the types of plastic used in them. Usually, the harder or more brittle the plastic, the rougher it is on the molds.
Molds are also sometimes constructed with a specific material in mind. Some of the gating might not work well if the viscosity of the melted plastic is greater than what it is designed to use. This probably won't be an issue, as I expect Nylon would be more viscous, but it's another unknown.
So it will probably boil down to whether they want to risk their molds, if they will work at all with the different material, and whether
there is a sufficient quantity to warrant the extra effort.
While they seem to be a company that will work with folks, as evidenced by the black player select buttons, this is really a much different scenario from the manufacturing side of things.
Keep your fingers crossed

RandyT