"Deploy Studio" is not LANDESK. I would bet that a Deploy Studio PXE server exists on the sub net you are attempting to boot on. Only one PXE server can exist.
What Kenyon said. Would capture the IP of the server that is responding and track with your networking team to who may own that. If it exists after you have setup a PXE rep on that subnet you are going to have a fun time with PXE roulette.