you have to understand that different ports are used in the network. A device is not either accessible or not accessible, but individual ports can be blocked or enabled for individual directions with a firewall.
Your admin explicitly blocked ping (trying to hide the printer)
He expressly allowed the ports required for printing. (some do that)
But there are different print services that use different ports for printing. (That’s outside of my comfort zone. I can’t help in detail there)