Greetings.
As long as the DB15 vga connector and the USB mouse/keyboard interface is standard, then I don't think the UCS server will care what device you have connected (i.e. physical KVM crashcart, your remote mgmt dell device). If the USB port or vga connector are proprietorially wired to only respond to dell devices (which I don't know to be true) then it would obviously not work.
I would make sure you simply configure the CIMC OOB management of the server as you will still get better remote vKVM functionality, virtual media mounting (ISOs), detailed health reporting, remote power control, etc, then you will out of the addon device you are showing.
Kirk...