Also remember that we don't always see the end result from the beginning of the journey. It is like a pebble dropped into a lake what starts as a small ripple can get bigger and bigger. Even though you didn't get the answer you wanted now, a seed may have been planted
I agree with AZ Scot. You have made it known your intent and desires, not only to your coworkers but also the management. Keep chipping away at their resolve at every opportunity and try to wear them down.

Of course, you could try to just wear it and force the issue. If it came down to it, I doubt they would fire you but it probably would seriously annoy them to have to deal with the confrontation (and potential discrimination). You would likely win a legal battle but I sense that you don't want that.

For the future, remember that it's easier to ask forgiveness than permission.