Color mode Greyscale doesn't reflect on client

I've set the color mode from our printer from 'Auto' to 'Greyscale':

It seems this change doesn't reach the Universal Print Class Driver on the client. The color mode remains 'Color':

I'm not able to change this setting via PowerShell, PrintTicket or fancy Registry changes. I just want that our user print in Black/White
by default. It woould be good to know if there is a known issue or I do something wrong.

Thanks.