Hi,
Mostly, 0xc0000001 may indicate network related issues. At the first state of PXE, TFTP is involved. For such random issue, it is suggested to use network trace tool to compare the working one and the problematic one and find out the clue accordingly.
If the environment is cross-subnet (assuming the netmask is 255.255.255.0 for below example picture), Microsoft recommends using IP helper, other than DHCP option (only for lab testing), you may involve the network guy for the network device configuration.
Regards,
Alex Zhu