Can you provide a clear screen shot of the problem taken with a mobile phone?
Also if you can follow the steps in this tutorial we can find out exactly what the target computer is being told to do. It really helps if the FOG server and target computer are on the same subnet to collect this pcap. https://forums.fogproject.org/topic/9673/when-dhcp-pxe-booting-process-goes-bad-and-you-have-no-clue